sustainability - building to meet the needs of the present generation without compromising the ability of future generations to meet theirs
green building - the practice of sustainable design and construction
global warming potential - total contribution to global warming
life cycle(LCA)/cradle-to-grave analysis - an environmental analysis of the effects of a building material beginning with extraction, continues through production and use, and finishes at end of life when disposed of or put to an entirely new use.
embodied energy - the sum total of energy consumed during the materials life cycle.
cradle-to-gate analysis - environmental analysis that begins with the extraction of material and extends onlyas far as when the material leaves the factory
embodied water - the fresh water consumedas a consequence of building with a particular material
embodied carbon - the total carbon related greenhouse gas emissions associated with a building material
LEED - Leadership in Energy and Environmental Design - Defines eight broad categories of sustainability goals which when achieved, qualify the applicant for LEED Certification by the Green Building Council. 1) Location and Transportation 2) Sustainable Sites 3) Water efficiency 4) Energy & Atmosphere 5) Materials & Resources 6) Indoor environmental quality 7) Innovation in design or operation 8) Regiona priority
LEED prerequisite - contributes points to the building's overall sustainability rating
LEED credit - contributes points to the building's overall sustainability rating
Living Building Challenge - a standard set by the International Living Building Institute. It aspires to mopve society beyond making buildings that do less environmental harm to conmstructing buildings that do no harm at all, and even provide benefit to the natural environment.
construction documents - Drawings primarily graphic in content and specifications are produced by the architect-engineer team to describe how the building is to be made and of what.
zoning ordinance - legal restrictions which govern the types of activities that may take place on a given piece of land, etc.
building code - protect public health and safety by setting minimum standards for construction quality, structural integrity, durability, livability, accessibility and especially fire safety
model building code - standardized codes that local jurisdictions may adopt for their own use. In Canada, the National Building Code is published by the Canadian Commission on Building and Fire Codes, In the US, the International Building Code is the predominant model code.
occupancy - IBC classification defines activities within a building A-Assembly, B -Business, E-Educational, F-Factory, H-High Hazard, I-Institutional, M-Mercantile, R-Residential, S-Storage, U-Utility
construction type - IBC codes for varying degrees of of resistance to fire. Type I Most Resistant to Type V - Least Resistant
Construction Specifications Institute (CSI) - organizing body of masterFormat data in the US
Construction Specifications Canada (CSC) - organizing body of masterFormat data in the Canada
MasterFormat - a comprehensive outline developed by CSI and CSC for organizing information about construction materials and systems. It is frequently used to organize construction cost data and it forms the basis on which most trade asociations and manufacturers tehmical literature is catalogued
UniFormat - an organizing outline contrasting with MasterFormat which organizes building systems information into functional groupings. A-Substructure, B-Shell, C-Interiors, D-Services, E-Equipment & Furnishings, F-Special Construction & Demolition, G-Building Sitework, Z-General
OmniClass Construction Classification System - an overarching scheme that attempts to incorporate existing systems, MasterFormat, UniFormat, and others into one system. Based on international standard ISO 120006-2 and continues to undergo active development.
design/bid/build - the owner first hires a team of architects and engineers to perform design services, leading to the creation of construction documents that comprehensively describe the facility to be built. Next construction firms bid on the project, the owner evaluates their proposals and awards the contract to the bidder deemed most suitable. Difficult to integrate design and construction
design/build - one entity assumes responsibiity for both design and construction. Fosters coordination between A/E and GC. Single ppint of accountability for owner.
construction manager - owner hires independent construction manager to oversee design & construction services by multiple entities. Construction expertise is available to owner throughout the project.
general contractor - the firm coordinating and overseeing the overall construction process
subcontractor - the person(s) performing the construction work
turnkey - owner contracts with a single entity that provides not only design and construction services, but financing for the project as well.
fixed-fee compensation, lump-sum compensation - the general contractor or other construction entity is paid a fixed amount to complete the construction of a project regardless of that entity's actual dosts to perform the work. • Owner pays an agreed, fixed amount for work to be performed • GC assumes most risk or potential reward for unplanned construction costs or savings • Best suited to projects where scope of work is well defined before construction starts • If scope is unknown, it is difficult to determine what the fixed, full cost should be" "
cost plus a fee compensation - • Owner pays GCs direct costs plus an added fee • Owner assumes more cost risk/savings reward potential • Well suited to projects where scope is not fully defined when construction begins • Adding a guaranteed maximum price (GMAX, GMP) limits the maximum cost and shifts some cost risk back toward the contractor"
guaranteed maximum price (GMAX, GMP) - 0
incentive provisions - used to more consistently align owner and contractor interests with financial rewards for timely completion of contract
surety bond - a bond to protect the owner for protection from risk of default such as bankruptcy by the construction contractor.
performance bond - a bond to assure completion of the construction
payment bond - a bond to assure full payment to suppliers and subcontractors
sequential construction - each major phase in the design and constructino of a building is completed nefore the nexct phase begins and construction does not start until all design work has been completed"
phased/fast track construction - aims to reduce the time required to complete a project by overlappng the design and construction of various project parts. Phased construction can introduce additional risks if elements built early come into conflict with later design decisions"
Gantt chart, bar chart - a chart in which a series of horizontal bars represent the duration of various tasks or group of tasks that make up the project
critical path - the sequence of activities that determines the least amount of time required to complete a project
float - The amount of time a task can be delayed without impacting the schedule.
critical path method - analyzes task dependencies in determining the critical path
lean construction - reduces complexity, eliminates wasteful activities, structures the supply of materials and methods of production to achieve the quickest and most reliable workflow, and decentralizes informatino and decision making to put control of processing into the hands of those most familiar with the work and most capable of improving it
building information modeling (BIM) - 3 - 4+ dimensional modeling of building systems
computer-aided design (CAD) - a 2 dimensional representation of building systems
system collision - a situation arising when the geometry of one design model, e.g., MEP engineering's ductwork, conflicts with another, say structural engineering's steel beams.
foundation - The below-ground components of the building devoted solely to the transfer of loads into the soil.
dead load - the combined weight of all permanent components of the building including the foundation itself.
live load - Non-permanent loads caused by the weights of the building's occupants furnishings and movable equipment
rain & snow loads - Loads acting primarily downward on building roofs
wind load - Loads acting laterally, downward, or upward on a building.
seismic load - Highly dynamic horizontal and vertical forces caused by the motion of the ground relative to the building during an earthquake
lateral soil pressure load - Horizontal pressures of earth and groundwater against basement walls
flood load - Lateral forces that can occur in areas prone to flooding
horizontal thrust - emanate from long-span structural components such as arches rigid frames domes vaults or tensile structures
buoyant uplift - forces from underground water identical to those that force a boat to float
settlement - action resulting from the compression and adjustment of the surrounding earth to the loads imposed by the building above
uniform settlement - settlement occurring at the same rate throughout all parts of the building
differential settlement - settlement occurring in different parts of a building at differing rates
earth material - for purposes of foundation design, earth materials are classified according to particle size, the presence of organic content and in the case of finer grained soils, sensitivity to moisture content.
consolidated rock or bedrock - a dense, continuous mass of mineral materials that can be removed only by drilling, fracturing, or blasting. Bedrock is generally the strongest and most stable material on which a building can be founded.
soil - a general term referring to any earth material that is particulate. Particulate soils are further defined according to ASTM D2487, United Soil Classification System as follows:
--boulders are greater than 12 inches (300 mm) in diameter.
--cobbles are smaller than boulders but greater than 3 inches (75 mm) in diameter.
--gravel is from 3 inches to 0.187 inches (75 mm to 4.75 mm) in diameter.
--sand is from 0.187 inches to 0.003 inches ( 4.75 mm to 0.07 mm) in diameter.
--gravel and sand are also collectively referred to as coarse-grained soils.
--silt particles are smaller than 0.0029 inches (0.075 mm). Like sand and gravel, silt particles are roughly spherical in shape.
--clay particles are also defined as smaller than 0.0029 inches (0.075 mm), though typically they are an order of magnitude (10 times) or more smaller. Also, unlike larger-grained particles, they are flat or plate-shaped rather than spherical.
--both silts and clays are also referred to as fine-grained soils.
organic soils - Organic soils are not suitable for the support of building foundations. Their high organic matter content makes them spongy and sensitive to changes in water content or biologivcal activity within the soil.
shear strength - The resistance of soils to internal sliding in supporting building loads. It varies with the degree of interlocking between particles and the confining force of the surrounding soil,.
frictional or cohesionless soil - Soils that rely primarily on internal friction for strength
soil pores - Spaces between soil particles
soil liquefaction - Condition in which water-saturated sands or silts lose virtually all their strength and behave as a liquid when subjected to sudden changes in load such as in an earthquake.
fabric - The name of the complex internal structure into which clay particles arrange themselves.
cohesive soil - Soils that tend to stick together such as clay. They tend to be hard when dry and moldable.
plastic soil - Plastic implies that the soil composition includes clay particles that produces a cohesive, puddy-like consistency when moist.
liquid limit - The moisture content at which soils develop a flowable consistency.
expansive soil - Soil that is prone to expand or contract with changes in moisture content. Clay soils may be expansive.
gradation - The range of particle sizes present in a soil sample.
well graded soil - Soil containing a broad well-distributed range of particle sizes
poorly graded soil - Soil containing a limited range of particle sizes
uniformly graded matl - Material composed of particles with a limited narrow size range
gap graded matl - Material containing a broader range of particle sizes, but with certain sizes omitted.
sorting - Used to describe the particle size distribution within a soil sample, but with the opposite direction of grading. i.e., well graded soil is poorly sorted and poorly graded soil is well sorted.
poorly sorted soil - Well graded soil
well sorted soil - Poorly graded soil
allowable foundation/soil pressure - The maximum pressure which can be applied at the soil/foundation interface by the foundation and the loads acting upon it
imported soil - Materials used for backfilling excavations, construction of base layers under pavements and concrete slabs at grade, finish grading for landscaping, or replacement of unsuitable native soils
native soil - Soil already present at the building site
consolidation - When clay with high moisture content are put under continuous pressure, water can be slowly pressed out of it resulting in a gradual reduction in soil volume, called consolidation.
general purpose fill - Well graded, course grained soil providing good compaction and stability
drainage fill - More porous than general purpose fill and of a more uniformly graded material.
test pit - Pits dug and used for observation of soil strata when the foundation will not extend deeper than 16 feet.
water table - The elevation at which the soil is normally fully saturated.
test boring - Borings can return information on each soil stratum, such as soil type, depth and thickness as well as groundwater conditions.
penetration sampler - Device used in test borings to determine soil density and potential load bearing capacity.
load test - Test performed to determine the load bearing capacity and stability of the soil.
sieve - Tool used in determining particle gradation of soil material being tested.
plastic limit - The water content at which soil transitions from solid to plastic
geotechnical report - Published results gained through subsurface exploration and laboratory testing.
brownfield site - A building site that was previously developed, damaged, or polluted.
brownfield site - A building site that was previously developed, damaged, or polluted.
grubbing and clearing - earthwork process in which trees and plants, stumps, large roots, and other surface materials are removed with heavy machinery.
benched excavation - Excavation method on sites sufficiently large or having cohesive soils such as still clays, to allow for excavation to be sloped back at a low enough angle that the soil will not slide back into the hole.
maximum allowable slope, angle of repose - The maximum slope for a benched excavation.
pneumatically applied concrete, shotcrete - A stiff concrete mixture that is sprayed directly onto the excavated soil. The hardened concrete reinforces the slope and protects against erosion.
shoring - Construction used to support the sides of an excavation and prevent its collapse.
H-pile / Soldier Beams - Steel columns driven vertically into the earth at close intervals around an excavation site before digging begins.
lagging - Heavy wood planks placed against the flanges of the steel columns
sheet piling or sheeting - Vertical sheets of various materials that are aligned tightly against one another edge-to-edge and driven into the earth before excavation begins.
soil mixing - Strengthening the sides of an excavation by blending portland cement and water with the existing soil
ground/earth improvement - Any of a variety of methods for altering properties of soil in place. E.g., soil mixing, or rammed aggregate piers.
slurry wall - A complex construction of a complete, steel-reinforced, concrete wall in the ground, many stories below the surface, before excavation takes place.
clamshell bucket - A bucket used in slurry wall operations for the removal of soil.
slurry - a viscous mixture of water and benzonite clay.
tremie - A funnel and tube arrangement for pumping concrete to the bottom of the slurry wall trench.
crosslot bracing - A method for bracing the excavation support system using temporary steel wide-flange columns driven into the earth where braces cross.
waler - Walers provide protection from cave-in of soil in an excavation trench
raker - Sloping rakers are used where excavation is too wide for crosslot bracing
tieback - Where soil conditions persist, tiebacks are used to provide support similar to rakers and crosslot bracing while maintaining a fully open excavation so that removal can continue
soil nailing - Process of stabilizing vertical walls of particulate soil. Similar to a rock anchor, a soil nail is inserted in a more dense pattern, effectively "knitting" together a large block of soil.
rock anchor - Used in excavations in fractured rock whereby anchors are drilled into the joints of the rock.
dewatering - Removal of water from the excavation to surrounding soil
sump - Pits in the excavation where water is collected for dewatering.
weil point - Vertical pipes inserted into the ground with screened openings at the bottom that keep out soil particles while allowing water to enter.
watertight barrier wall - Wall made from a slurry wall or soil-mixed wall used in cases where lowering of water table is ill advised.
soil freezing - An array of vertical pipes inserted into soil with circulating coolant to freeze the water in the soil around the insertion, thus creating a water barrier.
superstructure - The above ground portion of the building
substructure - The habitable portion below ground of the building
shallow foundation - A type of foundation which transfers building loads to the earth close to the base of the substructure.
deep foundation - A foundation using either piles or caissons to extend downward through layers of weak or unstable strata to reach more competent soil or rock.
spread footing - Spread footing takes concentrated loads from above and spreads them out across an area of soil large enough that the allowable soil pressure is not exceeded.
column footing - A square block of concrete with or without steel reinforcing that distributes a column to the soil below.
wall footing, strip footing - A continuous strip of concrete that distributes the load of a loadbearing wall to the soil below.
frost line - The level to which the ground freezes in winter.
ice lenses - Thick layers of ice that form as water vapor migrates upward from the soil and is trapped under the footing.
slab on grade - A simple and inexpensive spread footing for one and two story buildings in climates with little or no ground freezing.
crawlspace - Space below the building created by concrete or masonry walls resting on a strip footing
basement - Space created below the building by vertical walls.
tie beam - Tie beams maintain stability of the footings when subjected to lateral forces such as an earthquake.
combined/cantilever footing - For buildings built closely to the property line, this type ties the footings for the outside rows of columns to those of the next row in such a way that imbalance is neutralized.
shallow frost-protected foundation - Footings placed closer to the ground surface but insulated so the ground underneath them cannot freeze.
mat or raft foundation - In situations where the bearing capacity of the soil is low in relation to building loads, column footings would be so closely spaced that it is more effective to merge them into a single mat or raft foundation of heavily reinforced concrete 6 feet and more in thickness.
floating/compensated foundation - A mat type foundation placed at a depth such that the weight of the soil removed is close to the weight of the building constructed above, roughly 1 to 8.
caisson, drilled pier - Similar to a column footing in its function of spreading loads, iti differs in that it extends through strata of unsatisfactory soil until it reaches more suitable stratum.
belling - The process of flaring the bottom of the hole into which concrete is poured to form the caisson.
auger drill - Drills used for drilling caissons.
belling bucket - A special bucket attached to the auger drill used in the belling process.
belled caisson - A caisson that is flared or "belled" at the bottom to spread the load.
socketed caisson - A socketed caisson is one that is drilled into rock at the bottom, rather than belled.
pile - More slender than caissons and forcibly drilled into the earth rather than poured.
end bearing pile - A pile that is driven until its tip encounters firm resistance from a suitable bearing stratum.
friction pile - When a pile is driven into soil of fairly uniform consistency and the tip is not seated in a hard layer, the load-carrying capacity of the pile is developed by skin friction. The load is transferred to the adjoining soil by friction between the pile and the surrounding soil.
pile cap - Distributes the load of the column or wall above the piles.
driven to refusal - The point at which little additional penetration is made with continuing blows of the pile hammer.
grade beam - Reinforced concrete beams constructed between pile caps to transmit wall loads to the beams.
pile hammer - Weights used by the piledriver.
piledriver lead - Vertical rails on which the pile hammer travels.
piledriver - Pile driving machinery that operate by dropping weights on top of the pile to penetrate the soil and rock.
engineered fill - Properly formulated higher strength, more stable soil material brought from offsite to replace unsuitable native soil.
mat/raft foundation - For low load bearing soil, mat foundations effectively merge multiple closely spaced columns together to form a raft.
timber pile - Piles made from tree trunks with their branches and bark removed.
heaving - The upward displacement of adjacent soil during the pile driving process.
pipe pile - Piles made from steel pipe 8 to 24 inches or more in diameter either open or closed on the end.
minipile, pin pile, micropile - Steel bar or pipe 2 to 12 inches.
helical pile, screw pile - Similar toi minipiles but with one of more helical boring blades up to 24 inches in diameter.
precast concrete pile - Square, octagonal or round piles. May have open cores to allow for inspection. Most are prestressed.
sitecast concrete pile - Installed by driving a hollow steel shell into the ground and filling the shell with concrete. The shell may remain or be removed and reused.
pressure-injected/compaction grouted footing - A dry stiff mixture of concrete or grout is compacted into a pre-drilled hole. The compaction also densifies and strengthens the surrounding soil.
rammed aggregate pier/stone column - Similar to pressure-injected footing but are constructed solely with crushed rock.
base isolator - In earthquake prone areas, buildings are placed on base isolators which flex or yield to absorb a significant portion of the movement.
underpinning - The strengthening and stabilizing of an existing foundation by 1) enlarging existing foundation, 2) inserting new deeper foundation under existing, 3) strengthen soil by grouting or chemical treatment. Two methods, A & B, of supporting a building while carrying out underpinning work beneath its foundation follow:
up--down construction - If the building has several levels of basement, substructure may take many months or a year or more. In such a case up-down construction may be an economical option that allows for construction of the superstructure to procede during completion of the substructure.
drainage - Drainage typically consists of some combination of porous back-fill material, drainage mat, and perforated drain piping. The first example below relies solely on crushed stone placed against the foundation and is hard to do well because of the difficulty of depositing the drainage aggregate and backfill in neatly separated layers.
drainage mat - The drainage mat in the following example inculdes a drainage mat and is easier and often more economical to install. The mat is a manufactured sheet product usually about 1/2 inch thick made of very open, porous material.
filter fabric - Fabric that allows water to pass easily but prevents fine soil particles from entering and clogging drainage passages.
perforated drain piping - Piping, usually 4 to 6 inches, placed near the bottom of the foundation wall to carry water away.
cement plaster dampproofing, parge coating - Light gray in color and troweled on
dampproofing - Application of a moisture-resistant cement plaster or asphalt compound to basement walls where ground water conditions are mild or waterproofing requirements are not critical.
asphalt/bituminous dampproofing - Black in color and applied as a liquid by spray roller or trowel.
waterproofing - Unlike dampproofing, resists the passage of water even under the more demanding conditions of hydrostatic pressure.
liquid-applied membrane waterproofing - Materials applied by spray or roller as viscous liquids and allowed to cure in place.
bentonite waterproofing - Made from sodium bentonite, a naturally occurring highly expansive clay. Most often applied as preformed sheets consisting of dry clay sandwiched within corrugated cardboard, geotextile fabric, or plastic sheets.
sheet membrane waterproofing - Manufactured sheets more consistent in quality and thickness than liquid membranes. Difficult to apply around shapes and seams become most vulnerable in these systems.
integral waterproofing - Describes a variety of ingredients added directly to concrete when it is mixed to stop up the pores in the cured concrete and render the wall watertight.
electro-osmotic waterproofing - Electrical current flow intoduced to a concrete wall to drive water molecules toward the outer face.
radon (gas) - A cancer causing-gas that occurs naturally within soils.
passive radon control - Used to minimize gas infiltration into the building where radon gas risk is high.
active subslab depressurization - Installation of a fan to continuously draw air from underneath the building there reducing the risk of gas entry into the building.
retaining wall - Holds back soil where an abrupt change in ground elevation occurs.
earth reinforcing - As an alternative to a retaining wall, soil is compacted in layers, each sandwiched between strips or meshes of galvanized steel, polymer fibners, or glass fibers, which stabilize the soil.
gabion - A wirework container filled with rock, broken concrete, or other material, used in the construction of retaining walls
geotextile - Fabrics made of chemically inert plastics that are resistant to deterioration in the soil.
backfilling - Refers to the replacement of soil materials in an excavation to restore it close to its finished level.
soil lift - A layer of soil, 4 inches to a foot, which is added and then compacted in the process of filling.
controlled low-strength material (CLSM) - Manufactured fill material made from portland cement and/or fly ash, sand, and water. Also called "flowable fill" is delivered in concrete mixer trucks, poured into excavation, where it compacts, levels itself and hardens.
finish grading - Final leveling and smoothing of soil surfaces to their required contours and elevations.
mud slab - Weak concrete slabs, often composed of CLSM, used to create temporary, level, dry bases over irregular often wet excavations.
softwoods - softwoods come from coniferous trees. Most softwoods are cone-bearing with needle like leaves that remain on the trees during the colder winter months. The primary distinction from hardwoods lies in the microstructure,, consisting mainly of large tracheids together with a small percentage of radial cells (rays). Softwoods are less dense and softer than hardwoods.
hardwoods - Hardwoods are from broadleafed trees which shed their leaves in the winter months. The primary distinction from softwoods lies in the microstructure which is more complex with a larger percentage of radial cells (rays) and two different types of longitudinal cells (tracheids); small diameter fibers and large diameter vessels or pores.
tracheids - elongated cells in the xylem of vascular plants that serve in the transport of water and mineral salts
rays - sheets or ribbons extending vertically through the tree perpendicular to the growth rings. The cells in each ray are elongate and horizontal and are living cells, unlike the dead cells of the wood xylem. rays are essential for the radial conduction of the water, minerals and other organic substances.They transport the substances from centre to periphery
grain figure - the distinctive pattern that frequently results from various grain orientations in wood. Softwoods generally have a relatively course grain figure and hardwoods show finer, more attractive patterns.
lumber - lengths of squared wood used in production
roundwood - felled trees or logs
headsaw - log is passed repeatedly through headsaw which produces untrimmed slabs of lumber
plainsawn,flatgrain - Most structural lumber is plainsawn for the following reason. With plainsawn lumber, significant portions of the growth rings are oriented roughlyflat relative to the board's broader face, requiring the least repositioning of the log during sawing and producing the maximum yield of useful pieces, making it the most economical sawing method.
quartersawn, verticalgrain -
With quartersawn lumber, the growth rings are consistently aligned at an angle of approx. 45 degrees or steeper relative to the board's broader face.
Quartersawn softwood lumber is used for flooring, trim, siding and other types of finish woodwork where its advantages justify the added expense.
PROS: 1) More dimensionally stable boards, 2)More pleasing grain figure, 3) Flooring and Exterior Siding wear better-(no springwood)
CONS: 1) More handling, 2) Produces smaller pieces from same size log, 3) Generates greater waste
Hardwoods may be quartersawn, riftsawn, or plainsawn. A quartersawn hardwood board has growth aligned at an angle of approx. 60 degrees or greater to the board's broader face. A riftsawn hardwood board has growth rings aligned at an angle of roughly 30 to 60 degrees to the board's broader face.
structural grading - used to rate the strength and stiffness properties of a piece of lumber
visual grading - each piece is visually inspected for growth ring density and for growth and manufacturing characteristics, judged according to standard grading rules and marked accordingly.
machine grading/stress-rated - structural properties are assessed and stamped accordingly on the piece. Assessment is made by flexing each piece between rollers and measuring resistance to bending or scanned electronicaly to determine density.
species group, species combination - Much structurally graded lumber is rated by species group, that is, by collections of individual wood species that are sufficiently similar in their properties that they may be used interchangeably.
appearance grading - used to rank the visual qualities of lumber intended for flooring, trim, cabinetry, and other finish, nonstructural uses.
strength - The strength of a piece of wood varies with the direction in which the load acts in relation to the grain of the wood, the duratino of the stress, and the species and grade of the wood.
In any given orientation, wood is also normally stronger in compression than in tension, and stronger under short-term loading than under longer-lasting or permanent loads.
Comparative strengths of selected wood species and grades are displayed below:
physical properties - When designing a wooden structure, the architect or engineer determines the maximum stresses expected to occur in the various structural members and selects the appropriate species groups and grades from which to build.
The average structural properties of framing lumber compared to those of other structural materials - brick masonry, steel, and concrete - are displayed below. Of the four materials, only wood and steel have useful tensile strength.
Other factors that influence the useful strength of wood include, the temperature and moisture conditions under which it serves, and the size and shape of the piece.
nominal dimension - lumber sizes in the US are given in nominal dimensions in inches, such as 1 x 2 , 4 x 10, etc. Never includes inch marks when written.
actual dimension - the actual dimension of the lumber after sawing, i.e., a 2 x 10 usually measures 1 1/2 inches by 9 1/4 inches. Always includes inch marks when written.
boards - pieces of lumber that are less than 2 inches in nominal thickness
dimension lumber - lumber pieces ranging from 2 to 4 inches in nominal thickness
timber - pieces nominally 5 inches and mnore in thickness
board foot - a measurement based on nominal dimensions, not actual, used for pricing lumber. A board foot of lumber is defined as a solid volume 12 square inches in nominal cross sectional area and 1 foot long.
flitch - a log from which a veneer is taken is called a flitch.
veneer - wood produced in vey thin sheets - about 1/8 inch in thickness or less
rotary-cut veneer, rotary-sliced veneer - veneer produced by inserting a log into a large lathe and spinning the log against a long knife edge. Greatest use is in structural applications where appearance is not a primary concern. Most common application is in manufacture of structural plywood panels
plain sliced veneer - veneer produced by pressing a knife against a log without rotating the log. Produced grain patterns that are attractive for fine woodwork.
sawn veneer - veneer produced by sawing a piece without rotating the log as is the case with sliced veneer. Produced grain patterns that are attractive for fine woodwork.
sequenced veneer - veneers from the same log that are arranged in the finished work in the same order in which thay came from the log, matching grain patterns
glue-laminated wood, glulam - large wood structural members produced by joining many smaller strips of wood together with glue, glulam for short.
finger jointed or scarf jointed - Joints within a lamination of a glue-laminated beam, seen in the upper drawing in a small-scale elevation view, must be scarf jointed or finger jointed to transmit the tensile and compressive forces from one piece of wood to the next. The individual pieces of wood are prepared for jointing by high-speed machines that mill the scarf or fingers with rotating cutters of the appropriate shape.
hybrid glulam beam - beams that substitute composite laminated veneer lumber for the usually solid wood top and bottom laminations in the beam.
FRP reinforced glulam - capacity is increased by gluing a thin strip of high strength fiber reinforced plastic (FRP) between first and second lamoinations, nearest the edge of the beamn that acts in tension (usually the lower edge.
cross-laminated timbers (CLTs) - structural panels laminated from solid lumber, with the oprientation of members in each layer alternating from those above and below.
Structural composite lumber also called engineered lumber, products are substituted for solid lumber and are made from wood veneers, or wood fiber strands and glue.
structural composite lumber, engineered lumber - also called engineered lumber, products are substituted for solid lumber and are made from wood veneers, or wood fiber strands and glue.
laminated strand lumber (LSL), oriented strand lumber (OSL) - are made from shredded wood strands, coated with adhesive, pressed into a rectangular cross sec-tion, and cured under heat and pres-sure (the wood strands used in the manufacture of LSL are longer than those used in OSL). LSL and OSL are the least strong and least expen-sive of the composite lumber prod-ucts. They are used mainly for rim boards and short-span headers.
laminated veneer lumber (LVL) - made from thin wood veneer sheets, as wide as the member is deep, that are glued and laminated into thicker members. LVL is similar in appearance to ply-wood excep't without crossbands.
parallel strand lumber (PSL) - made from long, thin strips of wood veneer glued and pressed in a process similar to that for LSL and OSL, but with the veneer strips arranged more uniformly parallel than the strands in those other products. PSL is the heaviest, strongest, and most expen-sive of the composite lumber prod-ucts
structural finger-jointed lumber - short lengths of solid lumber scrap are finger-jointed and glued end-to-end into longer lengths.
l-Joist - used for framing of both roofs and floors (Figure 3.31). The top and bottom flanges of the members may be made from solid lumber, laminated veneer lumber, or laminated strand lumber. The thinner webs, which connect the top and bottom flanges, may be ply-wood or OSB. OSB is the most common choice because of its greater shear strength, an advantage in this application.
wood-plastic composite (WPC) - WPC products are made from blends of plastic with wood or agricultural fibers, usually in equal proportions. The mixture is heated and pressed, extruded, or injection-molded into final form. Compared to solid wood products, they offer more consistent material quality, freedom from defects and distortion, and superior resistance to moisture.
finger-jointed wood trim - made from short lengths of solid wood finger-jointed and clued into longer lengths, competes with WPC trim as an alternative to conventional finish lumber. More stable and consistently free of defects than solid lumber, it also makes productive use of short length scraps.
recycled plastic !umber (RPL) - lumberlike products made entirely or mostly from recycled plastic resins. RPL is resistant to sun, water, and insects; does not require protectuve coatings or finishes; and is non-toxic,durable and maintenance free. Because RPL is more flexible than solid wood it must be supported at more closely spaced intervals. And because it expands and contracts more with changes in temperature, it must be installed with greater allowances for thermal movement.
structural-grade plastic !umber (SGPL) - most commonly made from HDPE (high density polyethylene) reinforced with glass fibers and can be formulated to be at least as strong as conventional solid wood. Less stiff and more prone to long-term creep under permanent loads. SGPL planks, joists, beam, posts, piles, and other manufactured elements are used in the construction of decks, docks, piers, other types of exterior and marine structures, and even vehicular-capacity beidges.
structural wood panel - includes plywood, composite panels, and non-veneered panels
plywood - panels are made up of thin laters of wood veneer glued together. The grain on the front and back face weneers runs in the long direction of the sheet, shereas the grain in one or more interior crossbands runs perpendicular, in the shorter direction. There is alwals an odd number of laters in plywood, which equalizes the effects of moisture-relarted movements.
touch sanded - plywood panels intended for subfloors and floor underlayment are touchsanded to produce a flatter smoother surface.
medium-density overlay (MDO), high-density overlay (HDO) - For especially smooth and durable surface requirements, plywood is finished with a resin-treated overlay on one of both sides, for medium or high density protection
oriented strand board (OSB) - made of long shreds (strands) of wood compressed and clued into three to five layers. The strands are oriented in the same manner in each layer as the grains of the veneer layers in plywood. Because of the length and controlled orientation of the strands, OSB is the strongest and stiffest type of nonveneered panel. Because it can be produced from small trees and even branches, OSB is generally more economical than plywood. It is the material most commonly used for sheathing and subflooring of light frame wood buildings.
particleboard - manufactured in different density ranges, and is made up of smaller wood particles than OSB that are compressed and bonded into panels. It is used mainly as a base material for wood veneer and plastic laminate. Also used for an underlayment panel to create a very smooth base for the application of resilient flooring.
fiberboard - Very fine grained board made of wood finers and synthetic resin binders. It is generally limited to interior ues. The processing of the raw wood products in fiberboard nmanyfacturing is more intensive then in the manufacture of particleboartd, resuntint in a panel that is dimensionally more stable, stiffer, better to hold fasteners, and superior to its working and finishing charcteristics.
medium-density fiberboard (MDF) - The most commonly used form of fiberboard is medium-density fiberboard (MDF), used in the production of cabinets, furniture, moldings, paneling, and many other manufactured products.
Most nailed framing connections are made with common nails, box nails, sinkers, or their machine-driven equivalents. The more slender shafts of sinkers and box nails make them easier to drive than common nails and also good alternatives where splitting of the fastened pieces may be a concern (such as in a toe nailing).
Box nails are also used for fastening wood shingles and other types of siding.
Casing nails, finish nails, and brads are used for attaching finish components; their heads are set below the surface of the wood with a steel punch, and the holes are filled before painting.
Deformed shank nails, which are more resistant to withdrawal from the wood than smooth shank nails, are used for attaching sheathing, subflooring, and floor underlayment, materials that might otherwise work loose in service. The most common deformation pattern is the ring-shank pattern shown here.
Hardened-steel concrete nails can be driven into masonry or concrete for attaching furring strips and sleepers.
Cut nails, long ago used for framing connections, are still sometimes used for attaching finish flooring where their blunt ends punch through the wood rather than wedge through, lessening splitting of brittle woods.
Roofing nails have large heads to prevent tearing of soft asphalt shingles.
Standard common nails, reproduced here in their relative sizes.
The abbreviation "d" stands for penny. The length of each nail is given below this size designation, in both inches and millimeters.
The four sizes most used in light frame construction, 16d, 1 Od, 8d, and 6d, are shown shaded, with their shaft diameters also listed.
Some common screw types.
Flat-head screws are used without washers and are driven flush with the surface of the wood.
Round-head screws are used with flat washers and oval-head screws with countersunk washers.
Slotted head and Phillips head screws, driven by flat-blade and Phillips drivers, respectively, are the most common.
Self-drilling screws, such as the drywall screw shown here, do not require predrilled pilot holes.
split-ring connector - inserted in matching circular grooves to mate pieces of wood clamped tohether with a central bolt
timber rivet connection - formed by fastening steel plates to large wood members with spikelike rivets. Unlike nails, they are oval in crosssection and driven so that the wider axis of the rivet is always parallel to the grain of the timber. By driving arrays of rivets in closely spaced but carefully conttolled patterns, an area of wood becomes compacted and rprestreessed, creating a connection between the riveted plate and the wood that is stronger than possible with ordinary nails and less labor intensive than a bolted or split ring connection.
portland cement - The artificial cement product patented in 1824 by the English inventor Joseph Aspdin.
concrete - A rocklike material produced by mixing coarse and fine aggregates, portland cement, and water and allowing the mixture to harden.
aggregate - coarse to fine grained particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic material.
coarse aggregate - Normally gravel or crushed stone
fine aggregate - Sand
curing - The hardening process.
hydration - Throughout the curing, the cement combines chemically with water to form strong crystals that bind the aggregates together in a process called hydration.
heat of hydration - Heat generated from the hydration process.
drying shrinkage - Excess water evaporates during hydration causing the concrete to shrink slightly.
clinker - The raw materials are crushed, ground , proportioned and blended, then conducted through a long rotating kiln at 2600 to 3000 degrees to produce clinker. After cooling, clinker is combined with a small amount of gypsum which retards the later concrete curing process to come later. The resulting powder is portland cement.
air-entraining cement - Contains ingredients that cause microscopic air bubbles to form, thus improving workability and greatly increase the resistance to damage caused by repeated cycles of freezing and thawing.
white portland cement - Produced by controlling the quantities of certain minerals, such as oxides of iron and manganese, found in the ingredients of cement, that contribute to cement's usual gray color.
high-volume-fly-ash concrete (HVFA concrete) - When added to concrete, fly ash is most commonly substituted for portland cement at 15-25 percent. HVFA contains even higher percentages and research is undeway to develop concrete mixes in which portland cement is eliminated altogether.
structural lightweight aggregate - Made from minerals such as shale and meet the higher requirements of structural concrete.
expanded shale aggregate - A density of 25% less than normal concrete yet nearly as strong.
vermiculite - Expanded mica used in non-structural lightweight concretes.
perlite - Expanded volcanic gas used in non-structural lightweight concretes.
supplementary cementitious material (SCM) - Substituted for portland cement to achieve a variety of benefits.
pozzolan - Materials that react with the calcium hydroxide in wet concrete to form cementing compounds
fly ash - A fine powder that is a waste product from coal-fired power plants, increases concrete strength, decreases permeability, increases sulfite resistance,reduces amt of mixing water needed, improves pumpability and workability and reduces concrete drying shrinkage.
silica fume, microsilica - A powder 100 times finer than portland cement, consisting mostly of silicon dioxid and is a byproduct of electronic semiconductor chip manufacturing. Produces extremely high strength concrete with very low permeability
blast furnace slag, slag cement - A byproduct of iron manufacture is a hydraulic cement.
hydraulic cement - Like portland cement it reacts directly with water to form a cementious compound. Improves workability and strength, reduces permeability and temperature rise during curing, and improves sulfate resistance.
blended hydraulic cement - Product resulting from the combination of SCM's during the manufacture of portland cement. Half of more of concrete produced in the US contains SCMs.
(concrete) admixture - Ingredients other than SCMs added to concrete to alter its properties
air-entraining admixture - Increase the workability of wet concrete, reduce freeze-thaw damage, and in larger amounts, create very lightweight nonstructural concretes.
water-reducing admixture - Allows a reduction in the amount of mixing water while retainind the same workability
high-range water-reducing admixture, superplasticizer - Organic compounds that transform a stiff concrete mix into one that flows freely
slump test - A test performed at the time ofo pouring to determine if the desired degree of workability has been achieved.
slurry - a semistable mixture of solids suspended in liquid
segregation - Segregation occurs if concrete is vibrated excessively, or moved horizontally for long distances within the forms. It tends to segregate and the course aggregate works its way to the bottom and the water and cement paste rise toward the top.
consolidation - The procedure to elinminate trapped air and to complete fill the space around reinforcing bars and in all corners of the formwork.
self-consolidating concrete (SCC) - Formulated with more fine aggregates than course, a reversal of the usual proportions, and includes special superplasticizing admixtures
precasting - Process in which concrete is cast into reusable forms at an industrial plant and transported to the job site.
reinforced concrete - Concrete has no useful tensile strength and steel does, thus the fortuitous combination of concrete and steel to make reinforced concrete which combines the crushing strengrth of concrete with the tensile strength of steel.
welded wire reinforcing (WWR) or weided wire fabric (WWF) - A grid of wires or round bars spaces 2 to 12 inches apart uswed to reinforce concrete slabs on grade and certain pre-cast concrete elements.
vertical bar or column bar - large diameter bars that share the compressive loads with the concrete, resist tensile stresses, and impart ductility to the column
tie - small-diameter steel bars wrapped around vertical bars to help prevent them from buckling under load
column spiral - Tight coils of rod that are expanded accordian fashion to the required spacing and wired to the vertical bars.
column tie - discrete, closely spaced hoops, individually wired in place, used mostly to tie rectangular arrangements of vertical bars.
fibrous reinforcing - Composed of short fibers of glass, steel, or polypropylene that are added to the concrete mix.
microfiber reinforcing - Added in relatively low dosages to reduce plastic shrinkage cracking
macrofiber reinforcing - Usually of polypropylene or a steel-polypropylene blend, protects against plastic shrinkage and adds resistance to long term cracking due to drying shrinkage and thermal stresses. Can also improve resistance to impact, abrasion, and shock
creep - When placed under sustained compressive stress from its own weight, the weight of other permanent building components, or the force of prestressing, concrete will gradually and permanently shorten over a period of months or years.
prestressed concrete - The principle behind prestressed concrete is that compressive stresses induced by high-strength steel tendons in a concrete member before loads are applied will balance the tensile stresses imposed in the member during service
tendon - Tendons are high-strength steel strands used in posttensioning and are covered with a steel or plastic tube to prevent bonding to the concrete.They are not tensioned until the concrete has been poured and has achieved adequate strength.
camber - Camber is the lenthwise arching that takes place in the beam in pretensioning as a result of 1) the bonding of the concrete to the steel strand under tension and 2) the resulant arching of the strand when the are cut and the tension removed. The camber is reduce or flatten when the member is placed under load in the structure.
pretensioning - In pretensioning, the steel is stretched before the concrete is placed. High-strength steel tendons are placed between two abutments and stretched to 70 to 80 percent of their ultimate strength. Concrete is poured into molds around the tendons and allowed to cure. Once the concrete reaches the required strength, the stretching forces are released. As the steel reacts to regain its original length, the tensile stresses are translated into a compressive stress in the concrete. Typical products for pretensioned concrete are roof slabs, piles, poles, bridge girders, wall panels, and railroad ties.
posttensioning - In post-tensioning, the steel is stretched after the concrete hardens. Concrete is cast around, but not in contact with unstretched steel. In many cases, ducts are formed in the concrete unit using thin walled steel forms. Once the concrete has hardened to the required strength, the steel tendons are inserted and stretched against the ends of the unit and anchored off externally, placing the concrete into compression. Post-tensioned concrete is used for cast-in-place concrete and for bridges, large girders, floor slabs, shells, roofs, and pavements.
ACI 301 - Specifications for Structural Concrete for Buildings - In North America, concrete structures are required to be built according to these specs.
ultra-high performance concrete (UHPC) - Concretes with compressive strengths as high as 30,000 psi and that exhibit even usable tensile strength
pervious concrete - Made with gap or uniformly graded aggregate so that 15 to 30 percent of the finished concrete consists of open voids
light-transmitting concrete - Made from precast concrete blocks or panels with embedded optic fibers
slab on grade - a level surface of concrete that lies directly on the ground
capillary break - a layer of 1 1/2 inch-diameter crushed stone at least 4 inches deep
moisture barrier, vapor retarder - a heavy plastic sheet laid over the capillary break to further protect the slab from moisture in the ground.
strike off or screed - the first operation in finishing a slab whereby a stiff plank of wood or metal is drawn across the top edges of the formwork to achieve a level concrete surface.
floating - the process of flattening and consolidating the surface by drawing flat surfaced tools called bull floats or darbies, typically 4 to 10 feet in length, across the surface of the concrete.
bull float or darby - flat surfaced tool, typically 4-10 feet in length used for the initial floating
bleed water - The watery sheen on the surface of the slab.
troweled slab - If desired, a completely smooth, dense surface is accomplished immediately after the second floating using a smooth rectangular steel trowel.
steel trowel or rotary power trowel - tools used after the second floating to create a completely dense smooth surface.
knee board - squares of plywood on which the mason places his knees to distribute their weight over the slab surface
broom finish - a striated texture produced by drawing a stiff bristled push broom across the troweled slab
restraightening - process performed with 10ft straightedge to remove minor undulations produced during floating or troweling
straight edge - 10 ft flat bottom wooden on metal plank to be used for straightening
superflat (concrete) floor - Super flat floors are required by certain industries. These floors are specified according to a more complicated system of indexes, called F-numbers.
F-number - F-numbers correspond to the degrees of flatness(waviness) and levelness(conformity to a horizontal plane) required, and are produced using special finishing equipment and techniques.
control/contraction joint - intentionally weakened sections created through the concrete slab where the tensile forces caused by concrete drying shrinkage are relieved.
isolation/expansion joint - joint created by casting full-depth preformed joint materials, typically 3/8 to 3/4 inch in width into the slab in order to separate the slab from adjacent elements.
key - a groove formed in the top of the footing that will support a concrete reinforced wall. The key provides a mechanical connection to the wall and vertical steel dowels are inserted in the key.
dowel - steel reinforcing bars are installed in the footing to later be overlapped with the bars in the wall.
form tie - small diameter steel rods shaped to hold the formwork together under the pressure of the wet concrete, are inserted through holoes provided in the formwork panels and secured to the back of the form by devices supplied with the ties.
waler - A plank of wood, block of concrete, etc., used for support or to maintain required separation between components in order to help maintain the form of a construction under stress
stripped (formwork), formwork stripping - removal of formwork at appropriate time after pouring.
form tie hole - Hole left in concrete after removing form ties are filled with grout.
insulating concrete form (ICF) - ICF's serve to contain the concrete when the wall is poured and unlike conventional, become part of the wall for which they act as insulation in the range of R-17 to R-22
one-way solid slab - spans across lines of support furnished by walls or beams. The walls and columns are poured before the formwork for the slab is erected, but the forms for the girders and beams are nearly always built continuously with those for the slab and girders beams and slab are poured simultaneously as a single piece.
lift - Lift is the amount of concrete poured at each pour location such that after making pours at all, the first pour has had an hour or two to harden and is ready to receive another pour.
shore - adjustable length column that supports the girder and beam forms
reshoring - After slab and beams attain strength to support themselves, formwork is stripped & reshoring with vertical props is installed to relieve them of loads until they have reached full strength
slab band - One-way solid slabs are often supported by beams several times as broad as they are deep called slab bands. This is unlike normal concrete beams whose depth is twice or three times its breadth and the slab band offers two benefits. 1) Reduced thickness for the slab and consequent savings of concrete and steel. 2) Reduced depth of slab band allows reduction in story height of building and attendant economies in column, cladding, partitions, and vertical runs of piping and ductwork..
one-way concrete joist system, ribbed slab pan - One-way concrete joist systems provide significant benefits for spans larger than those for which one-way solid slab is appropriate. The primary benefit is the elimination of a significant portion of non-working concrete in the lower part of the slab with the introduction of joists or ribs to the slab profile.
distribution rib - A distribution rib is formed across a joist at midspan to distribute concentrated loads to more than one joist.
two-way flat slab - a system suited to heavily loaded buildings such as storage and industrial buildings. The formwork is completely flat except for a thickening of the concrete to resist high shear forces around the top of each column.
waffle slab, two-way concrete joist system - This is the two-way equivalent of the one-way concrete joist system in which metal or plastic pans called domes are used as formwork to eliminate nonworking concrete from the slab and to allow for considerably longer spans than are feasible with the two-way flat plate.
mushroom capital - A funnel shaped column capital providing the thickening required to resist high shear forces around the top of each column. Combined with drop panel capital if necessary. No additional reinforcing required beyond that provided by the column strip.
drop panel - a square shaped column capital providing the thickening required to resist high shear forces around the top of each column. Combined with mushroom capital, if necessary. No additional reinforcing required beyond that provided by the column strip.
column strip - Reinforcing strip designed to carry the higher bending forces encountered in the zones of the slab that cross the columns.
middle strip - Reinforcing strip between column strips containing lighter reinforcing pattern for lesser amounts of bending forces.
two-way flat plate - Two-way flat plate systems are used in more lightly loaded buildings such as hotels, hospitals, dormitories and apartment buildings. The slab in these buildings need not be thickened around columns, making the formwork more simple and even allows for the rearrangement of columns off the grid if necessary.
dome - Metal or plastic pans used as formwork to eliminate nonworking concrete from the slab.
head - Solid concrete heads are created around the tops of the columns by leaving domes out of the formwork in these areas. A head serves the same function as a drop panel in the two-way flat slab system.
hollow-core slab - precast elements suitable for intermediate spans in which internal longitudinal voids reduce dead-weight, non-working concrete.
double tee - precast elements suitable for the longest spans. T shaped design reduces dead-weight, non-working concrete.
single tee - precast elements suitable for the longest spans. Double-T shaped design reduces dead-weight, non-working concrete.
topping - For most applications, precast slab elements are manufactured with a rough top surface. After they have been erected, a concrete topping is poured over them and finished to a smooth surface.
L-shaped & Inverted Tee Beams - The projecting ledgers on these precast beams provide direct support for precast slab elements. THey conserve headroom by supporting slabs near the bottoms of beams, allowing the beam and slab to share the same structural depth. Precast columns are usually square or rectangular in section and may be prestressed or simply reinforced.
AASHTO Beam - AASHTO (American Association of State Highway and Transportation Officials) beams were designed originally as efficient shapes for bridge structures.
ledger - a horizontal support piece installed to support the ends of a structural component for a deck, a porch, or other structural system. Commonly installed to a concrete wall, or other vertical wall system, the ledger is provided to provide a bearing point for other structural members.
casting bed - permanent form in which precast concrete elements are produced
carbon fiber reinforcing - Because carbonfiber, unlike steel, does not require protection from corrosion, less concrete cover is required than for steel reinforcing, significantly reducing the overall thickness and weight of carbon fiber-reinforced components.
(hollow-core slab) extruded process - Extrusion devices squeeze an extremely dry stiff concrete mix through a moving extrusion die to produce the voided shape directly. Disadvantage of this method is that vertical openings cannot easily be cut in.
(hollow-core slab) wet-cast process - A bottom later of wet concrete is deposited in the casting bed; a second layer of concrete with collapsible tubes, dry crushed stone, or lightweight aggregate is positioned to create voids. Tubes or aggregate are removed after the concrete has cured.
(hollow-core slab) slip-form process - A moving hopper deposits a zero-slump concrete mix in the castingbed. Tubes that form the slab core move with the hopper and are pulled out of the slab as the casting process proceeds from one end of the slab to the other.
bearing pad - Bearing pads aer inserved at points of contact and serve to avoid the grinding, concrete-to-concrete contact that might create points of high stress while allowing for movement caused by expansion and contraction.
filigree precast concrete system - Relatively thin precast elements that are either conventionally reinforced or prestressed and used as the formwork for site casting of beams and slabs.
A - anchor bolt
B - weld or embed plate - furnishes a surface to which steel components can be welded
C - threaded stud
D - adjustable insert of malleable iron
E - threaded insert
F - threaded insert
G - dovetail slot
H - dovetailed wood nailer strip
I - steel railing post anchor
J - plastic sleeve
K - wood or fiber plug
L - lead sleeve
M - metal sleeve with nail insert
N - bolt with steel sleeve over tapered shank
O - special screw designed to grip tightly in concrete
P - special nail designed to grip tightly when driven in concrete
cement-lime mortar - The most characteristic typr of mortar made of portland cement, hydrated lime, an inert aggregate, and water. The aggregate, sand, must be clean and must be screened to eliminate particles that are too coarse or too fine.
lime - burnt limestone or sea shells (calcium carbonate) are burned in a kiln to drive off carbon dioxide leaving quicklime (calcium oxide). Lime adds workability or smoothness to mortar.
slaked/hydrated lime - calcium oxide(lime minus co2) that has been hydrated leaving calcium hydroxide.
blended hydraulic cement - portland cement + blast furnace slag
masonry cement - Prepackaged proprietary formulation not requiring the addition of lime on the jobsite. Air-entraining admixtures are added to achieve workability similar to cement-lime mortar. Because of the reulting higher air-content, masonry cement should not be specified for work requiring high strength and/or low permeability.
mortar cement - Pre-packaged cement not requiring the addition of lime on the jobsite. The difference from masonry cement is its limit on air-entraining admixture as stipulated by ASTM C1329 enabling mortar cements to meet bond strength requirements comparable to those of cement lime mortars.
Type N mortar - general-purpose mortar with a balance of good bonding capabilities and good workability recommended for exterior veneers, non-loadbearing exterior walls, parapets, chimneys, , an interior loadbearing walls.
Type S mortar - Higher flexural bond strength than Type N and recommended for exterior reinforced masonry, exterior loadbearing masonry walls, and veneers and walls subject to high wind forces or high seismic loads
Type O mortar - Low-strength mortar recommended mainly for interior nonloadbearing masonry and historic restoration work.
Type M mortar - A high strength mortar with less workability than Type S or N mortars. It is recommended for masonry construction below grade, masonry subject to high lateral or compressive loads, or masonry exposed to severe frost action.
workability - a general characteristic of wet mortar's usability: a workable mortar is smooth and plastic, easy to spread with a trowel, and adheres well to vertical surfaces.
proportion specification - #1 of two types of mortar mix specification in which the quantities of ingredients used to prepare the mix are specified
property specification - #2 of two types of mortar mix specification in which the compressive strength and orther properties of the hardened mortar as determined by laboratory testing are defined
hydraulic cement - cements that cure by chemical reaction with water, a precess called "hydration". Once hydraulic cements harden they become water insoluable.
lime mortar - lime mortar is made from a mix of lime, sand, and water and find use primarily in the restoration of historic structures. Lime is a non-hydraulic cement
nonhydraulic cement - mortars made with lime as the sole cementing ingredient, cured through a reaction with carbon dioxide, called carbonation,occuring gradually and continuing for many years.
carbonation - the curing process of nonhydraulic cements in which curing takes place by reaction with carbon dioxide and not water as is the case with hydraulic cements.
hydration - the curing process of hydraulic cements in which curing takes place by reaction with water.
retemper - the process to add workability to mortar which has become too dry to use. If mortar was mixed less then 90m minutes prior, it can be retempered by adding water. Mortar more than 2 1/2 hours old has begun to hydrate and must be discarded, because it has begun to hydrate and adding water will reduce final strength.
extended-life admixure - An admixture that extends the "safe" period for retempering to 72 hours.
set acclerator - admixture to help keep mortar from freezing when masonry work is done in very cold conditions
set retarder - admixture to help keep mortar from hydrating too quickly in hot water
integral water repellent - admixture to help make masonry walls more water repellent
efflorescence - the staining that forms on the surface of a wall when excess moisture carries minerals to the wall surface
soft mud process - relatively moist clay (20-30 percent water) is pressed unti simple rectangular molds by hand or with the aid of machines
water-struck brick - bricks resulting from a soft mud process in which the molds are dipped in water immediately before being filled with clay
sand-struck/sand-mold brick - bricks resulting from dusting the wet mold with sand before forming the brick
dry-press process - clay mixed with up to 10 percent water is pressed into steel molds by a machine at very high pressure.
stiff mud process - clay containing 12 to 15 percent water is passed through a vacuum to remove any pockets of air, then extruded through a rectangular die. As the clay leaves the die, textures or thin mixtures of colored clays are applied to the surface of brick.
periodic kiln - a fixed structure which is loaded with bricks, fired, cooled, and unloaded.
tunnel kiln - Tunnel kiln is a continuous moving ware kiln in which the clay products to be fired are passed on cars through a long horizontal tunnel. The firing of products occurs at the central part of the tunnel. The tunnel kiln is considered to be the most advanced brick making technology. The main advantages of tunnel kiln technology lie in its ability to fire a wide variety of clay products,better control over the firing process, and high quality of the the products.
water smoking/dehydration - the first stages of burning in a tunnel kiln during which remaining water is driven from the clay
oxidation - In an oxidation firing, ceramic wares are heated to a certain temperature. The heated ceramics draw oxygen from the kiln chamber and from the flue burner ports, spy holes and any other holes or cracks in the kiln. The oxygen combines with carbonaceous materials in the glazes and ceramic body, turning these into ash. Metal pigments in glazes, such as iron, will oxidize, giving the glaze a particular color.
vitrification - Vitrification is the transformation of a substance into a glass, that is to say a non-crystalline amorphous solid. In the production of ceramics, vitrification is responsible for its impermeability to water.
flashing - A fired visual effect on bare clay surfaces in fuel burning kilns (especially wood). ... A popular method is the application of slips having a makeup likely to react with the atmosphere or flame in the kiln.
fly ash brick - Bricks made from fly ash, a waste product from coal fired plants. The advantages of using fly ash brick are, the bricks carries good compressive strength, provide better thermal insulation than red clay bricks, cheaper compared to clay bricks and are environment friendly.
modular brick - The nearest thing in the US to a standard, brick is the modular brick. 4in vert. x 8in horiz.
Utility brick - brick having the same face height as a standard modular brick, but because it is longer in the wall cost is 25 percent lower and compressive strength of wall is about 25 percent higher because of smaller proportion of mortar.
facing/face brick - intended for both structural and nonstructural uses where appearance is important.
building brick - intended for use where appearance does not matter, such as in backup wythes of masonry that will be concealed in the finished work.
solid unit - a masonry unit whose net cross-sectional area in every plane parallel to the bearing surface is 75% or more of its gross cross-sectional area measured in the same plane.
cored unit - the CMU has two or three holes extending through the brick from the face. Designed to reduce the weight
frogged unit - the CMU has an indentation or depression in the face of a brick made for the purpose of holding mortar. There may be a single frog or multiple numbers of frogs on a face. Frogs may be shallow or deep with flat bottoms or with V- or U-shaped cross-sections
hollow brick - may be up to 60 percent void and are used primarily to enable the insertion and grouting of steel reinforcing bars in single wythes of brickwork
paving brick - for the paving of walks, drives and patios
firebrick - for the lining of fireplaces or furnaces
fireclay - produce bricks with refractory qualities or resistance to high temperatures
fireclay mortar - type of mortar used for laying firebricks which require very thin joints
brick grade - establishes minimum requirements for freeze-thaw durability, compressive strength and water absorption
brick type - Defines limits on the variation in size, distortion in shape, and chippage in facing brick only
chippage - extent of physical damage to face or visible corners
wythe - A wythe is a continuous vertical section of masonry one unit in thickness. A wythe may be independent of, or interlocked with, the adjoining wythe(s). A single wythe of brick that is not structural in nature is referred to as a veneer
header - a brick laid with its greatest length at right angles to the face of the work
course - a horizontal layer of bricks or other masonry units
bedjoint - a bedjoint is a horizontal joint in masonry
headjoint - a head joint is the vertical mortared joint between the side ends of brick or concrete masonry units.
collar joint - a collar joint is the vertical longitudinal space between wythes of masonry
stretcher - a brick laid with its face parallel to the wall and its long dimension horizontal
header - a brick laid so as to bond two wythes together
soldier - a brick laid on its end with its face parallel to the wall
rowlock - a brick laid on its face with its end visible in the wall face
structural bond - The method by which individual masonry units are interlocked or tied together to cause the entire assembly to act as a single structural unit.
common bond - (also known as American Bond) has a header every sixth course. The head joints are aligned between the hader and the stretcher courses.
Flemish bond - alternates headers and stretchers in each course.
English bond - alternates courses of headers of stretchers
cavity wall - a wall formed from two thicknesses of masonry with a space between them.
running bond - consists entirely of stretchers
lead - construction of a brick wall begins with the laying of lead bricks which establish the wall planes and course heights
story pole - a masons rule that is marked with the course heights and used to establish accurate course heights in the leads.
line block - wood or plastic blocks that fit around a corner or jamb. They're used to tie the line to leads or corner poles in order to lay each brick or block so its top is even with the line and its face is a trowel thickness away from the line
lay to the line - lay each brick or block so its top is even with the line and its face is a trowel thickness away from the line
tooled joint - a joint that has been finished according to the various tooling profiles
weathered joint - Mortar is recessed increasingly from the bottom to the top of the joint, with the top end not receding more than 3/8-inch into the wall
veejoint - along with concave joint, sheds water and resists freezing the best
concave joint - along with vee joint, sheds water and resists freezing the best
flushjoint - This joint is best used when the wall is intended to be plastered or joints are to be hidden under paint
raked joint - as does stripped joint, used to accentuate the pattern of bricks in the wall and deemphasize the mortar.
stripped joint - as does raked joint, used to accentuate the pattern of bricks in the wall and deemphasize the mortar.
struckjoint - This joint is formed in a similar fashion as the weathered joint, except that the bottom edge, instead of the top edge, is recessed. It is a very poor insulator against water, as it will allow water to collect on its bottom ledge
muriatic acid - used for giving the wall a final cleaning and then rinsed with water
lintel - a horizontal support of timber, stone, concrete, or steel across the top of a door or window
corbel - a structural piece of stone, wood or metal jutting from a wall to carry a superincumbent weight, a type of bracket
arch - a curved symmetrical structure spanning an opening and typically supporting the weight of a bridge, roof, or wall above it.
centering - framing used to support an arch or dome while it is under construction.
spandrel - A spandrel is the space between two arches or between an arch and a rectangular enclosure
gauged brick - brick molded, rubbed, or cut to an exact size and shape, for arches or ornamental work
rough arch - An arch constructed of ordinary bricks rather than cut or tapered stones
jack/flat arch - a structural element in masonry construction that provides support at openings in the masonry. Unlike regular arches, jack arches are not semicircular in form. Instead, they are flat in profile and are used under the same circumstances as lintels.
barrel vault - an architectural element formed by the extrusion of a single curve (or pair of curves, in the case of a pointed barrel vault) along a given distance.
dome - a rounded vault forming the roof of a building or structure, typically with a circular base.
buttress - a projecting support of stone or brick built against a wall.
reinforced brick masonry (RBM) - a loadbearing brick wall built by installing reinforcing bars in a thickened collar joint of 2-4 inches, then filling the joint with grout
grout - a mixture of portland cement, aggregate and water mixed to a consistency that flows easily
self-consolidating grout - a dry preblended grout specifically designed to be highly fluid without segregation of the constituents
low-lift grouting - grouting for masonry not greater than 4 feet before grouting.
high-lift grouting - grouting for masonry greater than 4 feet before grouting and the grouting is completed a story a time
cleanout hole - In reinforced masonry construc- tion, cleanout holes are the openings through which mor- tar droppings and other debris are removed and a wall is inspect- ed prior to high-lift grouting
tie - Wall ties connect one masonry wythe to an adjacent wythe
quoin - an external angle of a wall or building originally added to provide actual strength however more recently, added to simply create an impression of permanence and strength
igneous rock - rock that was deposited in a molten state
sedimentary rock - rock that was deposited by the action of water and wind
metamorphic rock - rock that was formerly igneous or sedimentary rock. Subsequently its properties were transformed by hear and pressure
Six Stone Groups - classified by ASTM C119 as : Granite, Limestone, Quartz-Based Stone, Slate, Marble, Other
granite - the igneous rock most commonly quarried for construction in North America. It is a mosaic of mineral crystals, principally feldspar and quartz, and can be obtained in a range of colors that includes grey, black, pink, red, brown, buff and green. Granite is nonporous, hard, strong, and durable and is the most nearly permanent of building suitable for use in contact with the ground or in locations where it ids exposed to severe weathering. Its surface can be finished in any of a nu7mebr of textures, including mirrorlike polish. Domestic granites are classified according to whether they are fine-grained, medium-grained, or course-grained.
basalt - like granite, basalt is a very dense and durable igneous rock. It is usually found only in a dark grey color, and is one of a group of stones that may be collectively referred to as black granites. It is generally used in the form of rubble and is seldom machined.
limestone - Limestone is one of the two principal sedimentary rock types used in construction. Colours range from almost white through grey and buff to iron oxide red. Limestone is porous and contains considerable groundwater when quarried. Some limestones can be polished (and may be classified as marbles), but most are produced with varying degrees of surface texture.
freestone - A freestone is a stone used in masonry for molding, tracery and other replication work required to be worked with the chisel. Freestone, so named because it can be freely cut in any direction, must be fine-grained, uniform and soft enough to be cut easily without shattering or splitting.
oolitic limestone - oolitic limestone is composed of calcium carbonate
dolomitic limestone - dolomitic limestone is composed of a mixture of calcium and magnesium carbonates
quarry sap - Groundwater trapped in limestone is called quarry sap when quarried.
sandstone - Sandstone is the second major sedimentary rock type used in building construction. Like limestone, it may be found either a strongly stratified form or as more homogeneous freestone. Formed in ancient times from deposits of quartz sand (silica dioxide), its color and physical properties car significantly with the material that cements the sand particles which may consist of silica, carbonates of lime, or iron oxide.
brownstone - a highly stratified and durable form of sandstone especially suitable for paving and wall copings.
bluestone - Slate is one of the wo metamorphic stone groups utilized in building construction. It is formed from clay. It is dense, hard stone with closely spaced planes of cleavage, along which it is easily split into sheets, making it useful for paving stones, roof shingles, and thin wall facings. Colors include black, grey, purple, blue, green, and red.
slate - Slate is one of the wo metamorphic stone groups utilized in building construction. It is formed from clay. It is dense, hard stone with closely spaced planes of cleavage, along which it is easily split into sheets, making it useful for paving stones, roof shingles, and thin wall facings. Colors include black, grey, purple, blue, green, and red.
marble - Marble is the second of the major metamorphic rock groups. In its true geologic form, it is a recrystallized form of limestone. It I easliy carved and poolished and occurs in white black and nearly every other color,often with beautifuol patterns of veining.
travertine - Travertine is a relatively rare, partially crystallized and richly patterned calcite rock deposited by ancient springs. It is marblelike in its physical qualities.
fieldstone - rough building ston obtained from riverbeds and rock-strewn fields.
rubble - irregular quarried fragments that have at least one good face to expose in a wall.
dimension stone - stone that has been quarried and cut into rectangular shapes.
cut stone - large slabs of dimension
ashlar - small rectangular blocks of dimension stone
flagstone - thin slabs of stone either rectangular or irregular in outline, used for paving and flooring.
jet burner - a tool for cutting granite, a stone much harder than other stones, which combusts fuel oil with compressed air.
spalling - the process of rock or stone breaking off in fragments
lewis - lewises permit the lifting and placing of blocks of building stone without interfering with the bed joints of mortar
petrographic analysis - microscopic examination of the stone's mineral content and structure
stone masonry - another name for stone facing attached to the structural frame or walls of a building.
stone cladding - masonry laid with continuous horizontal lines
coursed stone masonry - masonry laid with continuous horizontal lines
uncoursed stone/random stone masonry - masonry laid with no continuous horizontal lines.
quarry bed, grain - ashlar and rubble are usually laid with the quarry bed or grain of the stone running in the horizontal direction, because stone is oboth stronger and more weather resistant in this orientation.
stone veneer - Following is an example of a conventional method of anchoring blocks of cut stone facing to a concrete masonry backup wall. The metal strap anchors, which are in direct contact with the stone, should be made only of highly corrosion-resistant stainless steel. (When steel corrodes, it expands. Corrosion of the anchors where they engage with the stone could quickly cause damage to the stone itself.) The brackets attached to the concrete masonry backup wall may be stainless steel or less expensive galvanized steel. They are built into the concrete masonry backup wall as it rises. The airspace, or cavity, between the stone and concrete masonry creates a drainage plane that conducts water that penetrates the stone facing to the bottom of the cavity. The waterproof flashing at the base of the cavity forces the water to exit the wall back to the exterior through small drains in the facing called weep holes..
raked mortar joint - mortar joints in stone masonry are frequently raked (deepened) to a depth renging from 1/2 inch to 1 inch or more. If the mortar were to be included out to the face of the stone, there is good chance that outside edge would dry before the interior mortar and fall out. This allows the interior to dry properly and the mason returns to fill out to the face at that time with pointing mortar..
pointing mortar joint - pointing mortar forms a good weather seal at the face of the stone and is of Type O or N. It should never be of a higher strength of the mortar deeper in the joint.
clear sealer, water repellent - applied to protect the stone which is vulnerable to acids from air pollutants
Concrete Masonry Units, CMUs are manufactured in three basic forms: (1) large hollow units or concrete blocks, (2) solid bricks and (3) larger solid units.
CMUs are made in a variety of sizes and shapes in varying densities. The major ASTM standards under which concrete masonry units are manufactured are C90 for loadbearing units, C129 for nonloadbearing units, and C55 for concrete bricks. ASTM C90 establishes three weights of loadbearing concrete masonry units as shown below:
Designers layout buildings of concrete masonry in dimensional units that correspond to the block module in order to reduce cuts to a minimum.
Horizonrtal/joint reinforcing - welded grids of small diameter steel rods that are laid into the bed joints at set vertical intervals.
3 Types of Lintels for concrete block walls - Following are examples of Lintels for openings in concrete masonry walls. At the top, a steel lintel for a broad opening is made up of a wide-flange section welded to a plate. Steel angle lintels are used for narrower openings. In the middle, a reinforced block lintel is composed of bond beam units. At the bottom, a precast reinforced concrete lintel is seen.
dry-stacked/surface bonded CMU - walls constructed by stacking CMUs in a running bond directly upon one another without the application of mortar.
decorative/architectural CMUs - easily and economically manufactured in an unending variety of surface patterns, textures, and colors intended for exposed use on interior and exterior walls.`
structural glazed facing tile - used heavily until the 1950's and replaced by plaster, gypsum board, and concrete masonry. Still encountered and used in the restoration of older buildings.
structural terra cotta - glazed or unglazed molded decorative units of fired clay
glass block - glass blocks are non absorbent and the mortar stiffens more slowly than it does with more absorbent units of clay or concrete, so temporary spacers are inserted between uhits to maintain proper spacing until mortar sets up
autoclaved aerated concrete (AAC) - ingredients aresand, lime, water, and aluminum powder. When reacted with steam produce a relatiely light-weight, aerted concrete. Because of its trapped has bubbles created by the aluminum powder reaction with lime, density of AAC is similar to wood and is easily sawed, drilled and shaped. Too porous to be left exposed so they are usually stuccoed on exterior and plastered on interior.
composite masonry wall - uses different masonry materials in different parts of the wall construction to achieve an aptimum balance between appearance longevity and economy in the completed wall.
cavity wall - interposes a hollow vertical space within the wall to intercept water that penetrates the outer wythe.
Masonry Ties & Joint Reinforcing #1
Masonry Ties & Joint Reinforcing #2
Masonry Ties & Joint Reinforcing #3
flashing - thin impervious membrane at the bottom of the cavity
weep hole - a small opening that allows water to drain from within an assembly.
dampproofing - a type of moisture control applied to building walls and floors to prevent moisture from passing into the interior spaces
masonry loadbearing/bearing wall - does double duty by serving as exterior walls and interior partitions.
Avg linear coefficients of thermal expansion for some masonry materials
One system for posttensioning a concrete masonry wall
ordinary construction - floors and roof are framed with wood joists and rafters and supported at the perimeter on masonry walls…the fabric of which American center cities were built in the 19th century.
Ordinary Construction with Cavity Wall of brick with a concrete masonry loadbearing wythe(Top)
Ordinary Construction with Cavity Wall of brick with a concrete masonry loadbearing wythe(Middle)
Ordinary Construction with Cavity Wall of brick with a concrete masonry loadbearing wythe(Bottom)
heavy timber/mill construction - like Ordinary construction, combines masonry exterior walls with a wood frame interior. However, it uses heavy timbers rather than light joists, rafters, and studs, and thick timber decking rather than thin wood panel sheathing and subflooring
nonmovement joint - joints used to connect pieces of material in a building and can be made to move only by overloading the joint, such as slippping steel members in a bolted connection or the cracking of a weld.
movement joint - joints with a designed ability to adjust to expected amounts of motion without stress
working join t - the simplest movement joints designed into various building materials and created in the normal process of assembling a building.
structure/ enclosure joint - separates structural from non-structural elements so that they will act independently. E.g., the deflection track at the top of a metal framed interior partition to allow the structure above to deflect without imparting loads into nonbearing wall framing.
isolation joint - separates materials or assemblies that must be abvle to move independently.
control joint - deliberately created lines of weakness along which cracking will occur as the surface of brittle material shrinks.
expansion joint - open seam that can close and open to allow expansion and contraction to occur in adjacent areas of material
building separation joint - divides a large or geometrically complex building mass into smaller discrete structures that can move independently of one another. Three types: volume-change, settlement, and seismic separation.
volume-change joint - relieves the effect of expansion and contraction caused by temperature and moisture and are placed at horizontal or vertical dicsontinuities in the massing of the building where cracking would be most likely to occur
settlement joint - designed to avoid distress caused by different rates of anticipated foundation settlement
seismic separation joint - used to divide a geometrically complex building into smaller units that can move independently during an earthquake
efflorescence - a flufy crystalline powder, usually white, that sometimes appears on the surface of a wall of brick, stone or concrete masonry consisting of water-soluble salts that were originaly present in the masonry units or mortar and brought to the surface by water seeping into the masonry
spall - the solitting off or flaking of mortar caused by water running down a wall, accumulating in the joints, and then cycling through freezing and thawing.
repointing, tuckpointing - the process of raking and cutting our the defective mortar and replacing it with fresh mortar.
steel - steel is any of a range of alloys of iron that contain less than roughly 2 percent carbon.
mild steel - ordinary structural steel containing less than three-tenths of 1 percent carbon, plus traces of beneficial elements manganese and silicon, and traces of detrimental impurities phosphorus, sulphur oxygen and nitrogen
cast iron - a hard, relatively brittle alloy of iron and carbon that can be readily cast in a mold and contains a higher proportion of carbon than steel (typically 2.0–4.3 percent)
wrought iron - Wrought iron is an iron alloy with a very low carbon (less than 0.08%) content in contrast to cast iron (2.1% to 4%). It is a semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight), which gives it a "grain" resembling wood that is visible when it is etched or bent to the point of failure. Wrought iron is tough, malleable, ductile, corrosion-resistant and easily welded.
ferrous metal - any iron-based metal
iron ore - rocks and minerals from which metallic iron can be economically extracted
smelting - the process of extracting a metal from its ore thru heating and melting.
blast furnace - A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. Blast refers to the combustion air being "forced" or supplied above atmospheric pressure.
coke - coke results from the process of driving off impurities from coking coal leaving almost pure carbon.
slag - stony waste matter separated from metals during the smelting or refining of ore.
basic oxygen process - a hollow, water cooled lance is lowered into a container of molten iron along with recycled steel scrap amounting to 25-35% of total. A stream of pure oxygen at very high pressure is blown from the lance into the metal to burn off the excess carbon and impurities. A flux of lime and fluorspar is added to the metal to react with other impurities, particularly phosphorus, and forms a slag that is discarded. Added manganese gives resistance to abrasion and impact, molybdenum gives strength, vanadium imparts strength & toughness, and nickel & chromium give corrosion resistance, toughness, and stiffness.
mini-mill - mills producing structural steel from virtually 100 percent recycled scrap utilizing elecrtric arc furnaces.
electric arc furnace - An electric arc furnace is a high-temperature furnace that uses high-voltage electric arcs to make steel. Electric arc furnaces are a feature of the so-called mini-mills that recycle iron and steel scrap into new steel products.
beam blank, bloom - very thick approximations of the desired final shape, which are then rolled into final form
high-strength, low-alloy steel - High-strength low-alloy steel (HSLA) is a type of alloy steel that provides better mechanical properties or greater resistance to corrosion than carbon steel. HSLA steels vary from other steels in that they are not made to meet a specific chemical composition but rather to specific mechanical properties.
weathering steel - HSLA stands for high-strength low-alloy steel. It is a type of carbon steel that has small amounts of alloying elements added to its chemical composition. The alloying elements are used primarily to increase the strength of the steel. In addition to being able to provide increased strength over carbon steel, HSLA steel can also be made to have higher toughness and be more responsive to heat treatment. The alloying elements can also be used to increase the corrosion resistance of the steel.
stainless steel - stainless steel, also known as inox steel or inox from French inoxydable (inoxidizable), is a steel alloy with a minimum of 10.5% chromium content by mass. Stainless steels are notable for their corrosion resistance, which increases with increasing chromium content.
quenching - the process of rapid cooling
tempering - the process of partial reheating
structural mill, breakdown mill - in these mills, the beam blank is reheated as necessary and then passed through a succession of rollers that squeeze the metal into progressively more refined approximations of the desired shape and size.
hot saw - the saw that cuts segments from the continuous length shape exiting the structural mill
cooling bed - area in which cut segments are cooled
roller straightener - corrects any residual crookedness in the cut segments
(steel) bar - round, rectangular, and hex solid shapes not greated than 8 in. (203mm) in any cross-sectional dimension
(steel) plate - wide solid shape thicker than a sheet
(steel) sheet - wide solid shape not as thick as a plate
wide-flange shape - the shape used for most beams and columns.
cast steel - steel produced by pouring molten steel into molds and allowing the steel to cool. Cast steel is especially well suited for the production of custom-shaped connections for steel structures that are stronger, lighter, and more attractive than possible with those fabricated from conventional rolled steel.
cold-worked steel, cold-formed steel - steel that is rolled or bent in a cold state (room temperature). Steel is cold-drawn through dies to produce the very-high-strength wires used in wire ropes bridge cables, and concrete pre-stressing strands.
hollow structural section (HSS) - also called structural tubing, they are often used for coluns and for members of welded steel trusses and space trusses.
open-web steeljoist (OWSJ) - a truss mass-produced from cold and hot-rolled shapes usedin closely spaced arrays to support floor and roof decks.
joist girder - Joist girders are designed to allow for the efficient use of steel in longer spans. Various weight tables developed by the manufacturers list joist girders from 20 inches to 96 inches deep and spans up to 100 feet. The standard configuration of a joist girder is parallel chords with underslung ends and bottom chord extensions.
rivet - a rivet is a steel fastener consisting of a cylindrical body and a formed head. It is brought to a white heat in a forge, inserted while hot through holes in the members to be joined, and hot worked with a pneumatic hammer to produce a second head opposite the first.
high-strength bolt - high-strength bolts are heat treated during manufacturing to develop their greater strength,In contemporary steel frame construction, bolted structural connections rely almost exclusively on high-strength bolts.
carbon steel bolt - carbon steel bolts find only limited use in bolted structural connections such as in the fastening of minor framing elements or temporary connections
snug-tight - in bearing-type connections, bolts need only be installed to a snug-tight condition in which movement between the joined members is resissted by the bolts themselves as the sides of the bolt holes in the connected members bear against the bodies of the bolts. Under normal load-conditions, bolts in bearing-type connections are stressed primarily in shear.
(bolt) preloading - in slip-critical connections, the process of tightening bolts to such an extent that friction between the adjoining faces of the steel members (the faying surfaces) resists movement between the members. Under normal laod conditions, boltsin slip-critical connections are stressed in tension.
faying surface - A faying surface is one of the surfaces that are in contact at a joint. Faying surfacesmay be connected to each other by bolts or rivets, or by adhesives or welding or by soldering.
galling - damage caused by preloaded bolts to the surfaces of the joined members. Washers may be required to prevent this.
impact wrench - an electeic or pneumatic wrench for tightening bolts. In slip critical conditions, bolts must be tightened to at least 70% of their ultimate tensile strength.
turn-of-nut method - bolt is tightened snug then turned a specified additional fraction of a turn.
load indicator washer, direct tension indicator (DTI) - washer that has protrusions that are progressively flattened as the bolt is tightened
calibrated wrench method - to verify bolt tension,sometimes a special torque control wrench is used to tighten bolts.
tension control bolt - bolts with protuding splined ends that extends beyond the threaded portion. Nut is tightened by special power driven shear wrench that turns the bold and spline against one another. When the required torque is reached, the spline breaks off.
electric arc welding - An electrical potential is established between the steel pieces to be joined and a metal electride. When the electrode is held close to the seam between members, a continuous electric arc is established that generates sufficient heat to melt both a localized area of the steel members qnd the tip of the electrode. The molten steel from the electrode merges with that of the members to form a sibgle puddle. The electrode ids drawn slowly along the seam, leaving behind a continuous bead of metal that cools and solidifies to form a continuous connection between the members.
weld symbol - The required thickness and length of each weld are calculated by the designer to match them to the forces to be transmitted between members, and are indicated on fabrication drawings using standardized weld symbols
backup bar, backing bar - small srrips of steel welded veneath the groove before the actual weld is begun, to prevent the molten metal from flowing out the bottom of the groove.
demand-critical weid - welds in structural connections that may be subjected to very high stresses during a seismic event and that are critical to maintaining the stability of the building structure
shear connection - A shear connection is capable of transferring vertical forces (shear) from a beam to a columnmoments from a beam to a column. However, because it does not connect the beam flanges to the column, it is of no value in transmitting bending forces (bending moment) from one to the other.
framed connection - A shear connection in which the beam is connected to the column by angles
moment connection - A moment connection is capable of transmitting bending forces between a beam and a column because the beam flanges connect to the column by means of full penetration groove welds. If the column flanges are insufficiently strong to accept the forces transmitted from the beam flanges, stiffener plates must be installed inside the flanges of the column to better distribute the forces into the column.
bending moment - A bending moment is the reaction induced in a structural element when an external force or moment is applied to the element causing the element to bend.
full-penetration groove weid - a groove weld in which the entire member cross-section is welded without protruding from the other side.
braced frame - braced frame uses diagonal bracing to create stable triangular configurations within the rectilinear geometry of the frame.
eccentrically braced frame - a special case of the braced frame in which the ends of diagonal braces are offset some distance from each other where they connect to horizontal members.
shear walls - very stiff walls made of steel, cponcrete or reinforced concrete masonry. They act in much the same way as the diagonal bracing within a braced frame structure and like the braced frame permit the use of shear connections between beams and columns in the remainder of the frame.
moment-resisting frame - a moment resisting frame has neither shear walls nor diagonal bracing but relies on moment connections between beams and columns to provide lateral stability.
rigid core - the arrangement of stabilizing elements as a rigid core structured as a stiff tower using diagonal bracing and shear walls. The remainder of the building is then constructed with shear connections, relying on the core for lateral stability.
rigid perimeter, tube structure - diagonal bracing, shear walls or beam to column moment connections are incorporated into the outer walls of the building frame and the entire interior structure is assembled with simpler shear connections.
Fully-Restrained moment connection - a connection that is sufficiently rigid that the geometric angles between members will remain virtually unchanged under normal loading
Partially-Restrained moment connection - a connection not as rigid as Fully Restrianed but nonetheless possesses a dependable and predictabkle moment resisting capacity
Simple connection - Otherwise known as shear connections and are considered to be capable of unrestrained rotation under normal loading conditions and to have negligible moment-resisting capacity. Buildings framed solely with simple connections must depend on diagonal bracing or shear walls for lateral stability.
seated connection - a connection with a bracket or 'seat' on which the beam rests.
end plate connection - a connection in which a plate welded to the end of the beam is attached with bolts to the column.
simple connections - otherwise known as shear connections,mare considered to be capable of unrestrained rotation under normal loading conditions and to have negligible moment resisting capacity.
Exploded view of a bolted beam-to-column-flange (AISC Simple) connection
Two elevation views of a bolted beam-to-column-flange (AISC Simple) connection
A bolted, framed beam-to-column-flange shear (AISC Simple) connection
A seated beam-to-column-web (AISC Simple) connection.
A single-tab shear (AISC simple frame) connection
A coped beam-girder shear (AISC simple) connection
A coped beam-girder shear (AISC simple) connection,
A Series of Column Connections
Fully Restrained (FR) moment connections - FR connections are sufficiently rigid that the geometric angles between members will remain virtually unchanged under normal loading.
Partially-Restrained (PR) moment connections - PR connections are not as rigid as FR connections, but nonetheless possess a dependable and predictable moment-resisting capacity that can be used to stabilize a building frame
A welded moment (AISC Fully Restrained) connection
A welded beam-to-column-web moment (AISC Fully-Restrained) connection
A welded/bolted end plate beam-column (AISC Partially-Restrained) connection.
fabricator - the fabricator designs connections to transmit the loads indicated by the engineers drawings. The completed shop drawings are submitted to engineer and architect for review. Upon approval the drawings are turned into structural steel elements in the fabricators shop.
plasma cutting - cutting device using high temperature ionized gas and fully automated to cut and shape parts from digitally prepared models.
laser cutting - cutting device using lasers and fully automated to cut and shape parts from digitally prepared models.
camber - The slight upward curve given the form of beams and girders that is designed to deflect into a near horizontal under load.
erector - the erector is responsible for assembling into a frame on the building site the steel components furnished by the fabricator.
ironworker - the traditional name given the erectors workers
baseplate - baseplates distribute the concentrated loads of steel columns across a larger area of the concrete foundation..
leveling plate - plates set perfectly level at the proper height on a bed of grout atop each concrete foundation on which the baseplate attached to each column is attached.
grout - a bed of grout is placed between the leveling plate and the foundation
raising gang - the name for the ironworkers working with a crane and positioning the components to be bolted, squared and plumbed
plumbed up - straightened and squared
luffing-boom crane - The luffing-boom crane was designed to meet the requirements of the restricted job site. With a short tail-swing and the ability to raise and lower its boom, it easily adapts to construction site demands providing complete coverage while avoiding obstructions. Compact tower systems result in a minimal footprint for both interior and exterior climbing operations.
hammerhead boom crane - The "hammerhead", or giant cantilever, crane is a fixed-jib crane consisting of a steel-braced tower on which revolves a large, horizontal, double cantilever; the forward part of this cantilever or jib carries the lifting trolley, the jib is extended backwards in order to form a support for the machinery and counterbalancing weight
tagline - tagline is the name of the rope attached to the end of the element to be positioned and held by the ironworker guiding it.
topping out - topping out is the name given to the placement of the last beam at the top of the building.
metal decking - a thin sheet of steel that has been corrugated to increase its stiffness
cellular decking - decking manufactured by welding two sheets, one corrugated and one flat to provide additional stiffness to support normal floor loads without structural assistance.
vented metal decking - metal decking manufactured with small slotted openings comprising roughly 1 percent of the overall decking area and often used where impermeable roofing membranes are installed over lightweight insulating concrete fills to allow excess moisture to escape downward through the decking.
puddle weld - metal decking is usually puddle welded to joists, beams, and girders by melting through the decking to the supporting members below with a welding electrode.
composite meta! decking - metal decking designed to work together with the concrete floor to make a stiff lightweight economical deck. Special rib patterns in the sheet metal bond with the cement and provide tensile reinforcing for the concrete.
shear stud - steel studs or 'Nelson' studs are welded every few inches to the top of each beam to create a strong shear connection between the concrete slab and the steel beam.
subpurlin - a light architectural member resting on purlins and usually running at right angles to them. A purlin is a secondary roof framing member that supports other smaller members. In a panelized roof system, purlins are supported by main carrying members. The purlins, in turn, support stiffeners (sub-purlins) that provide support framing for the structural panel deck.
girt - horizontal z-shapes or channels that span between the outside columns of the building
Methods for fireproofing steel columns. (A) Encasement in reinforced concrete. (B) Enclosure in metal lath and plaster. ( C) Enclosure in multiple layers of gypsum board. (D) Spray-on fireproofing. (E) Loose insulating fill inside a sheet metal enclosure. ( F) Water-filled box column made of a wide-flange shape with added steel plates.
Methods for fireproofing steel beams and girders. (A) Encasement in reinforced concrete. (B) Enclosure in metal lath and plaster. ( C) Rigid slab fireproofing. (D) Spray-on fireproofing. (E) Suspended plaster ceiling. ( F) Flame-shielded exterior spandrel girder with spray-on fireproofing inside.
castellated beam - The castelated beam is produced by flame-cutting the web of a wide-flange section along a zig-zag or arced path, then re-assembling the beam by welding its two halves point to point thus increasing its depth and not its weight.
plate girder - plate girders are custom designed and fabricated for supporting long span beams. Steel platesd and angles are assembled by bolting or welding in such a way so to put the steel exactly where it is needed.
rigid steel frame - rigid steel frames are produced bywelding together steel wide-flange sections or plane girders.
steel truss - A steel truss is a triangular arrangement of steel members that are generally deeper and lighter than improved beams and can span correspondingly longer distances. They can be designed to carry light or heavy loads.
staggered truss system - the staggered truss system relies on story-high steel trusses staggered on alternating floors of a building structure and spanning berween perimeter columns to support the floors and roof.
space truss, space frame - A space truss or space frame is a truss made three dimensional and carries its load by bending along both of its axes much like a two-way concrete slab. It must be supported by columns that are spaced more or less equally in both directions.
cold-formed metal framing - sheet metal is fed from cotinuous coils through machines at room temperature that cold-work the metal and fold it into efficient structural shapes.
stud or joist section, C-section - for wall, floor, and roof framing
track section - for top and bottom plates
channel section - for lighter bracing and framing tasks
furring channel - for lighter bracing and framing tasks
self-drilling screw - screws used for joining light gauge steel members which drill their own holes and form helical threads in the holes as they are installed. Driven rapidly by hand-held electric or pjeumatic tools these screws are plated with cadmium or zinc to resist corrosion.
web stiffener - used to prevent buckling in floor joists, paticularly those that support load bearing studs
gypsum sheathing panel - gypsum panels used for sheathing exterior walls. They are similar to gypsum wallboard but made more resistant to moisture and weather with glass mat faces and specially formulated water-resistant gypsum cores.
nonstructural metal framing - light gauge steel members used for framing interior partitions and other nonloadbearing applications
thermal bridge - Light gauge steel framing has a high level of thermal conductivity and therefore must be detailed and insulated to minimize thermal bridging in cold regions.
A thermal bridge is an area or component of an object which has higher thermal conductivity than the surrounding materials, creating a path of least resistance for heat transfer. Thermal bridges result in an overall reduction in thermal resistance and unwanted heat transfer into or out of conditioned space.
halftimbering - braced wall framing with exterior wall members exposed on the face of the building
wattle and daub - crude plaster of sticks and mud
cruck - curved timber hewn by hand from appropriately shaped trees
Type IV Heavy Timber (HT) construction - A construction type from the International Building Code requiring that wooden structural members meet minimum size requirements and exterior walls be constructed concrete, masonry, a steel frame with metal or other noncumbustible cladding.
Mill construction, Slow-burning construction - the combination of fire-resistive wood framing and noncombustible exterior
chamfer - the process of eliminaitng from timbers the thin edges of wood that catch fire most easily by adding a 45 degree bevel edge
hinge connector - a connector used for connecting beams at points of zero bending moment rather than at the columns to take advantage of continuous bending action in the beams
firecut - a firecut is the angled cut applied to timber roof or floor beams such that in a prolonged fire, the beam will safely release from the supporting column and not topple the wall above it,
floor & roof decks - Building codes require that Type IV Heavy Timber buildings have floors and roofs of solid wood construction without concealed combustible cavities. The following image displays four different types of decking used for that purpose.
bent - a bent is an assembled plane of columns, beams, rafters & braces prepared for raising into final position.
purlin - secondary framing members that span across the primary beams or rafters.
shear connector - in wood concrete composite systems, sheer connectors installed in the upper face of the timebr beams or CLT (cross-laminated timber) panels, so that after concrete has cured, the connectors will engage with both the wood and concrete so that under structural loading the components will share stresses.
rigid frame - Rigid frames are glue-laminated to shape and find wide use in longer span buildings. Rigid frames exert a horizontal thrust, so they must be tied together at the base with steel tension rods, also called tie rods.
heavy timber truss - The joints for heavy timber trusses are made with steel bolts and welded steel plate connectors, split-ring connectors, or other proprietary hardware. Sawn laminated and structural composite timhers may be used, sometimes in combination with steel members.Spans of more than 100 feet are possible.
knife plate - metal plate spanning the joint between members to create high strength connections.
heavy timber arch or dome - Long curved timbers for making arches and domes are easily fabricated in laminated wood and are widely used in athletic arenas, auditoriums, warehouses and factories. Like rigid frames, these structures exert lateral thrusts that must be countered by tie rods or suitable designed foundations.
balloon frame - Balloon framing is a style of wood-house building that uses long, vertical 2" x 4"s for the exterior walls. These long "studs" extend uninterrupted, from the sill on top of the foundation, all the way up to the roof. Fireblocking is required in balloon frame to close the cavities in the wall against the passage of fire.
joist - a length of timber or steel typically arranged in parallel series to support a floor or ceiling.
stud - an upright support in the wall of a building to which sheathing, drywall, etc., are attached.
rafter - one of several internal beams extending from the eaves to the peak of a roof and constituting its framework
fireblocking - The purpose of fire blocking is to prevent fire from spreading through the concealed spaces of a building. It works by dividing framing cavities into separate compartments, slowing the passage of flames and combustion air.
platform frame - Platform framing (also known as western framing) is the most common framing method for residential construction where each floor of a pole barn or conventional building is framed independently by nailing the horizontal framing member to the top of the wall studs.
sheathing - A layer of boards or of other wood or fiber materials applied to the outer studs, joists, and rafters of a building to strengthen the structure and serve as a base for an exterior weatherproof cladding
rim joist - In the framing of a deck or building, a rim joist is the final joist that caps the end of the row of joists that support a floor or ceiling
sub floor - a rough floor laid as a base for a finished floor.
sole plate, bottom plate - a horizontal timber at the base of a wall frame.
top plate - a horizontal timber at the top of a wall frame.
ridge board - in a sloping roof, the ridgeboard is a horizontal timber at the peak of the roof
header - Load bearing member that supports the load over an opening such as a door or window
cripple stud - Short framing stud that fills the space between the header and top plate or the sill and sole plate
sill - a shelf or slab of stone, wood, or metal at the foot of a window or doorway
trimmer stud - Vertical framing member that forms to the sides of rough openings for doors & windows. Stiffens the frame and supports the weight of the header
o.c. , on center - indicates that the given dimension applies to the distance between the center of one member to the center of the next member
batter boards - temporary frame corners, set beyond the site stake of a planned foundation at precise elevations. These batter boards are then used to hold layout lines (construction twine) to indicate the location of the foundation.
When the foundation is complete, basement beams are placed, sills are bolted to the foundation, and the first-floor joists and subfloor are installed.
Plywood sheers are considerably stiffer along their length than across their width so they must be laid with their long dinension perpendiculat to the joints. The end joints are staggered to acoid lines of weakness.
The subtloor makes a convenient platform on which to assemble the first-tloor wall frames. The assembled frames are tilted up into place, nailed to the floor and to one another, and supported by temporary braces.
When the first floor walls are complete and sheathed, much of the temporary bracing can be removed. The second floor platform is framed the same as the first, with its joists resting on the double top plates of the first floor walls.
Interior stairways are usually framed as soon as the upper-floor platform is completed. This gives the carpenters easy up-and-down access during the remainder of the work. Temporary treads of joist scrap or plywood are nailed to the stringers. These will be replaced by finish treads after the wear and tear of construction are finished.
The ceiling joists above the second floor (which also serve as the attic floor joists) are toenailed to the tops of the second floor walls. A few rafters are then erected to support the ridge board, and remainder of the rafters are put up. Double headers and trimmers are used around openings in the roof.
A roof framing plan for the building. The dormer and chimney openings are framed with doubled header and trimmer rafters. The dormer is then built as a separate structure that is nailed to the slope of the main roof.
cripple stud - Short framing stud that fills the space between the header and top plate or the sill and sole plate
let-in diagonal bracing - Nominal 1 inch-thick boards applied into notched studs diagonally that are installed by the framer at the rough stage to give support to an exterior wall or wall corner.
hold-downs - Holdown refers to the steel device or hardware that is installed at the bottom of a plywood shear wall. The holdowns provide uplift resistance against the overturning moment imposed on the wall due to "in-plane" lateral load applied at the top of the wall.
shear wall - a shear wall is a structural system composed of braced panels (also known as shear panels) to counter the effects of lateral load acting on a structure. Shear walls resist in-plane loads that are applied along its height.
collector, drag strut, drag tie - components that transfer lateral forces from larger areas, such as floors or roofs, to the parts of thestructure designed to resist those forces, such as the shear walls.
ridge beam - A ridge beam is a structural member used to support the ends of the rafters at the ridge, transferring it's loads to posts or gable end walls.
pitch - pitch, or slope, is specified as a ratio of rise(vertical dimension) to run (horizontal dimension). In the US, potch is usually given as inches of rise per foot of run.
framing square - a large carpenters square graduated with scales typically for use in cutting off and notching rafters and stair joists.
hip - The hip is the external angle at which adjacent sloping sides of a roof meet.
valley - The "V" shaped area of a roof where two sloping roofs meet. Water drains off the roof at the valleys.
hip rafter - the rafter extending from the wall plate to the ridge and forming the angle of a roof hip
valley rafter - the rafter extending from the wall plate to the ridge and forming the angle of a roof valley
pattern rafter - a pattern rafter is laid out by the head carpenter for each type of rafter in the roof and serves as a template for erectors when cutting all other rafters.
dormer - A dormer is a roofed structure, often containing a window, that projects vertically beyond the plane of a pitched roof
common rafter - A common rafter is one of a series of sloped structural members that extend from the ridge or hip to the wall plate, downslope perimeter or eave, and that are designed to support the roof deck and its associated loads
ridge board - the ridge board aligns the tops of the rafters and supports the top edges of the roof sheathing
collar tie - collar ties near the ridge on steep roofs prevent uplist of the roof pane in high winds
valleyjack rafter - A valleyjack rafter is a shortened common rafter that framed to a valley rafter.
hip jack rafter - A hip jack rafter is a shortened common rafter that framed to a hip rafter.
fascia - Fascia is a vertical frieze or band under a roof edge on which spouting is often attached.
rake - the sloping edge of a gable or shed roof
steep roof - usually defined as one whose slope is MORE than 2:12 or 17 percent.
low-slope roof - usually defined as one whose slope is LESS than 2:12 or 17 percent.
roof deck - the structural surface that supports the roof.
thermal insulation - slows the passage of heat into and out of the building
air barrier - restricts the leakage of air through the roof assembly
vapor retarder - prevents moisture vapor from condensing within the roof assembly
roof membrane - the impervious sheet of material that keeps water out of the building
flashing - thin pieces of impervious material installed to prevent the passage of water into a structure from a joint or as part of a weather resistant barrier (WRB) system
ponding - areas of water remaining on a low slope roof that does not drain properly
substrate board - the substrate board as the material that is placed upon the roof deck prior to the placement of thermal insulation. It often is used in part to support vapor retarders and air barriers
topside vent - provides ventilation for vapor trapped under the roof membrane. Ventilated low-slope roof assemblies are most effective with roof membranes that are not fully adhered to the layers below, allowing entrapped moisture to more easily find the vents.
protected membrane roof (PMR) - in a PMR system, insulation is installed above the membrane offering two advantages, the membrane is protected from extremes and the membrane is on the warm side of the insulation where it is immune to vapor blistering problems.
ballast - crushed stone or gravel on the top level of the PMR which holds down the layers below and protect them from sunlight
thermal resistance (R, RSI) - a materials effectiveness in resisting the conduction of heat is called its thermal resistance, abbreviated as R and expressed as square foot-hour-degree Fahrenheit per BTU. The higher a materials R-value, the higher its resistance to heat flow and the better its performance as a thermal insulator.
relative humidity - the amount of water vapor present in air expressed as a percentage of the amount needed for saturation at the same temperature.
dew point temperature - the temperature at which a volume of air is fully saturated with water vapor.
vapor pressure - the pressure exerted by water vapor on the surfaces of objects containg it.
vapor retarder, vapor barrier - a vapor retarder is a material used to slow the diffusion of water vapor through a building assembly.
vapor permeance - a measure of a materials resistance to water vapor diffusion
perm - premeance is measured in perms defined as the passage of one grain of water vapor per hour through 1 square foot of material at a pressure differntial of 1 inch of mercury between the two sides of the material.
vapor permeability - not to be confused with vapor permeance, vapor permeability is defined as a material's vapor permeance for a unit of thickness.
lightweight insulating concrete - economical insulating material that creates a nailable roof deck, formulated with lightweight aggregates or air-entraining agents, this material has densities ranging from 20-40/lb/ft3 compared to 145 lb/ft3 for conventional concrete.
insulation coverboard - made of materials similar to those used for substrate boards and placed over the rigid insulation prior to installation of the roof membrane. Protects the insulation from damage by foot traffic, increases fire resistance and separates the membrane from incompatible insulation materials.
bitumen - a black viscous mixture of hydrocarbons obtained naturally or as a residue from petroleum distillation. It is used for road surfacing and roofing.
bituminous roof membrane - a roofing membrane composed of asphalt or coal-tar pitch sandwiched between layers ofroofing felt
built-up roof (BUR) membrane - BUR is assembled in place from multiple layers of asphalt-impregnated roofing felt bedded in layers of hot bitumen. The felt is made from cellulose, glass, or synthetic fibers and is saturated with asphalt at the factory. The felts are laminated in overlapping layers, with the hot bitumen welding them into a membrane two to four piles thick. To protect the membrane from sunlight and physical wear, a layer of crushed stone or other mineral granules is embedded in the top surface.
modified bitumen roof membrane - made from factory manufactured sheets of polymer modified bitumens or asphalt materials, to which compounds have been added to increase materials flexibility, cohesion, toughness, and resistance to flow. Sheets are assembled in place in overlapping layers to form a membrane two or three plies thick. Sheets are bonded by one of the following methods.
torch-applied modified bitumen membrane - as a sheet is unrolled, an open flame apparatus thermally fuses the underside to the topside of the underlying sheet.
hot-mopped modified bitumen membrane - application of hot asphalt to bond sheets
cold-applied adhesive modified bitumen membrane - uses liquid adhesives to bond sheets
self-adhered modified bitumen membrane - relies on factory applied adhesives to bond sheets
cap sheet - the surface composed of mineral granules and other materials applied to the top of modified bitumen roof.
hybrid membrane bituminous roof - a combination of built-up and modified bitumen systems, with a modified bitumen cap sheet applied over several piles of built up roofing.
single-ply roof membrane - membrane sheets come in rolls in widths ranging from 3 to 20 feet. They are affixed to the roof deck by adhesives, the weight of ballast, or fasterners concealed in the seams between sheets.
fluid-applied roof membrane - used for domes, shells and other complex shapes that are too flat for shingles or too steep on sides for builtup membranes. Fluid applied membranes are installed with a roller or spray gun.
traffic deck - Traffic decks are installed over flat roof membranes for walks, roof terraces, and driveways or parking surfaces. Two different systems are used:
In one plastic pedestals are placed on top of the roof membrane to support the corners of square paving stones or slabe with open joints.
In the other the drainafe layer of gravel or pervious concrete is leveled over the membrane, and open-jointed paving blocks are installed on top.
To protect the membrane from accidental damage, a protective layer of roof membrane is frequently placed over the membrane before the traffic deck components are installed.
low-slope roof details - Roof slopes and drain locations are arranged to ensure positive drainage throughout the roof. Crickets and saddles are locally sloped surfaces used to divert water around obstructions in the roof or create slope in level areas
base flashing - Any metal or composition flashing at the joint between a roofing surface and a vertical surface, such as a wall or parapet.
fascia - a vertical frieze or band under a roof edge, or which forms the outer surface of a cornice, visible to an observer
scupper - an outlet in the side of a building for draining water.
parapet - a low protective wall along the edge of a roof, bridge, or balcony.
counterflashing - the piece of metal that is applied to the masonry wall designed to shed water off of the wall and down onto the roof surface
coping - the top course of a brick or stone wall
cant strip - a beveled strip used under flashings to modify the angle at the point where the roofing or waterproofing membrane meets any vertical element.
nail base - a nailable surface for the finish roofing provided by plywood or OSB fastened over the insulation boards.
wood shingle - this tapered slabs of wood sawn from shorrt pieces of tree trunk with the grain of the wood running parallel to the face of the shingle
wood shake - thicker than shingles, wood shakes exhibit a rougher texture and are frequently split from the wood rather than sawn
skip sheathing, spaced sheathing - spaced boards running perpendicularly across sloped roof rafters to which wood shingles and shakes are attached.
breather mat - a wiry plastic mat placed under shingles creating a thin airspace that provides airflow reducing potential condensation and deterioration of the shingles.
asphalt shingle, composition shingle - diecut from heavy sheets of asphalt impregnated felt faced with mineral granules to act as a wearing layer and decorative finish.
valley - a valley is formed where two sloping roof planes meet above an inside corner of the building.
open valley, woven valley, cut valley - three methods applying shingles to a valley in a steep sloped roof
roll roofing - produced from the same material as asphalt shingles in rolls 3 feet wide. Used primarily on utility and agricultural buildings.
slate shingle - slate shingles are delivered to the site split, trimmed to size and punched or drilled for nailing. Slate roof typically lasts 60 to 80 years
clay tile - used on roofs for thousands of years, these tiles traditional to the Mediterranean region are available both glazed and unglazed.
concrete tile - generally less expensive than clay tiles and availablie in some of the same patterns. Estimated lifetimes range from 30 to 75 years.
oil canning - visible waviness in the flat areas of metal roofing and metal wall panels. In technical terms, oil canning is referred to as elastic buckling more commonly known as “stress wrinkling”.
flat-seam metal roof - Flat seam roofing is constructed of rectangular cold rolled metal sheets. Two adjacent sides of the sheets are folded over and two are folded under to form 3/4" locks. Copper cleats of 16 or 20 oz. cold rolled copper are installed in each of the longitudinal and transverse seams. The finished pans are interlocked longitudinally and transversely, with staggered transverse seams.
standing-seam metal roof - the seams are joined where the metal roofing sheets meet, and the seam stands above the surface of the panel level. Standing seams are a generalized concept and refer to a specific type of metal roof that makes use of standing seams in its design. In fact, standing seams have a variety of different designs and can look very different from one another.
batten-seam metal roof - batten seams make use of an underlying framework where the metal panels are mounted between a raised batten strip and a cap is used to cover the seam. Batten seams are commonly used in architectural designs and are highly effective in water removal due to these roofs typically having sloped or pointed designs. These roofs also offer high levels of wind resistance.
lead - soft easily formed very longlasting metal that oxidizes overtime to a dull white color. It is also toxic to humans and its use in nuilding materials is discouraged. Wherei t is encountered, special health precautions are required during its handling.
copper - a relatively soft metal that turns blue-gren in clean aid and a dignified black in an industrial atmosphere; various chemical treatments can nbe used to ontin and preserve the desoired color
lead-coated copper - historically used to combine the greater strength of copper with the gray-white color of lead and to avoid the staining of wall materials buy oxides of copper that can occur with rainwater runoff from uncoated copper roofs. As noted earlier, the presence of lead in building materials is discouraged by green building programs.
zinc - long-lasting roofing metal made of zinc alloyed with small amounts of copper and titanium to improve its workability. It normally ages to a dark gray color and can also be treated in various ways to alter or preserve its appearance.
stainless steel and titanium - strong and long-lasting but less easily worked than other roofing metals. Both are silvery-white.
zinc-tin alloy coated stainless steel - has a darker duller appearance than uncoated stainless steel. This material is very similar in appearance to-and is sometimes equated with-a lead-tin alloy coated metal called terne-coated stainless steel that is no longer manufactured but may still be found on older buildings.
gauge, gage - a system of numbers in which lower numbers correspond to greater metal thickness. Sheet metal standards now specify metal thickness in decimal or fractional inches. The exception is copper which is specified by weight, expressed in ounces per square foot.
solar reflectance, albedo - the measure of a material's tendency to reflect solar radiation rather than absorb it.
thermal emittance - the measure of a material's capacity to radiate infrared heat energy and cool itself as its temperature rises.
solar reflective index (SRI) - the measure of solar heating potential that accounts for a material's reflective and emittive properties, as well as for its ability to lose heat through thermal conductance to the surrounding air.
cool color - non-white roofing materials that reflect a significant portion of the suns radiation. Cool colours are formulated with pigments that are selectively reflective to different portions of the solar spectrum. They are highly reflective of near-infrared (NIR) radiation.
near-infrared (NIR) radiation - an invisible component of solar radiation that accounts for more than half of the total hear energy radiated by the sun
green roof, vegetated roof - roofing systems covered with vegetation, soil and additional materials needed to support plant growth.
extensive green roof - relatively shallow roofs with soil depths of 2 to 6 inches, low-maintenance, drought tolerant plants, moderate roof loads
intensive green roof - roofs with soil depths as deep as 30 inches and are designed to support a broader variety of plant types and shrubs, Irrigation and plant maintenance required, greater roof loads..
flood test - test for green roof membranes by submerging them for a period of hours or days to check for leaks prior to placing the overlying components.
modular green roof system - a module containing all the components of the green roof system abive the membran are preassembled in easily transported trays typically 2-4 feet in plan dimension and 2-8 inches in depth.
plate glass - first produced in the late 17th century, molten glass is cast into frames, spread into sheets by rollers, cooled, then ground flat and polished with abrasives to a near perfect optical quality in sheets of unprecedented large size Mechanizatiion of the grinding process in teh 19th centuryreduced the price of plate glass to a level that allowed it to be used for storefronts in both Europe and America..
float glass - Float glass is a sheet of glass made by floating molten glass on a bed of molten metal, typically tin, although lead and various low melting point alloys were used in the past. This method gives the sheet uniform thickness and very flat surfaces. Produced in North America since 1963, float glass now accounts for nearly all domestic glass production.
annealing lehr - An annealing lehr is a temperature-controlled kiln for annealing objects made of glass. The resulting objects have less internal stress and thus are less prone to breaking.
single-strength glass - glass with a thickness ranging from 3/32 in through 1/8 in.
double-strength glass - glass with a thickness ranging from 1/8 in. through 1 in.
annealed glass - Regular float glass cooled slowly to reduce in built stress
heat-treated glass - produced by reheating annealed glass in an oven to approximately 1150 degrees Fahrenheit and then cooling (quenching) both of its surfaces rapidly with blasts of air while its core cools much more slowly.
quenching - the rapid cooling of a workpiece in water, oil or air to obtain certain material properties.
tempered glass, fully tempered glass - Tempered Glass or toughened glass is manufactured through a process of extreme heating and rapid cooling, tempered glass is much harder and is four times stronger than annealed glass. Another benefit of tempered glass is the ability to stand up to moderate heat (470°F).
Tempered glass cannot be drilled or cut without shattering. All fabrication needs to be done while the glass is in the softer, annealed condition.
Annealed glass can be cut, drilled, notched and edge finished. Tempering is only done once the shaping and fabrication is complete.
heat-strengthened glass - Glass which is reheated, after forming, just below melting point and then cooled. A compressed surface is formed which increases its strength. Used for spandrel glass.
laminated glass - Two or more sheets with an inner layer of transparent plastic, polyvinyl butyral (PVB), to which the glass adheres if broken. Used for overhead, safety glazing, and sound reduction.
polyvinyl butyral (PVB) interlayer - the transparent layer in laminated glass
security glass - made of multiple layers of glass and PVB. It is available in a range of thicknesses to stop any desired caliber of bullet.
damage weighted transmittance (Tdw) - a range of values, 0 to 1, that quantify the overall effect of UV and visible light on the fading and degradation of interior finishes, fabrics and some types of artwork. A wall opening without any glazing inserted has a Tdw of 1…an opaqu e material that blocks the passage of all light, a Tdw of 0.
chemically strengthened glass - produced by an ion exchange process that takes place whe annealed glas is immersed in a molten salt bath. Because of lower temps used, does not exerience the optical distortions or warping that hare common with heat treated glass. Unlike tempered glass, this glass can be cut after strengthening.
CPSC 16 CFR Part 1201 - establishes two categories of performance for safety glazing
Category II glazing - Category II glazing is required to have a higher impact resistance than Category I
Category I glazing - Establishes glazing requirements for larger pieces and for pieces in what are considered more hazardous locations.
ANSI Z97.1 - ANSI standard requiring that safety glazing be permanently etched in factory with an indicaiton of its testing compliance so that once installed it is possible to verify that appropriate products have been used where required.
fire-rated glass - may be used in two situations: in traditional role within fire doors and fire windows or, with jmore recently available higher performing glass products as a complete sunstitute for rated wall assemblies.
fire-protection rated glazing - glazing that meets minimum requirements for resisting the passage of smoke and flame for a required duration. Fire protection rated glazing used in fire doors must achieve ratings of 20 to 90 minutes and glazing in fire windows must achieve ratings of 20 to 45 minutes.
wired glass - used for glazing in fire windows and doors before the introduction of specially tempered glass or optical-quality ceramics.
fire-resistance rated glazing - more stringent tests than are applied to fire rated glazing. In addition to preventing the passage of flame and smoke for the prescribed period of time,the glazing must also protect cobustible materials on the side of the glaing opposite the fire from ignition by blocking radiant heat and limiting the rise in surface temperature of the glass itself on its non-fire side.
fritted glass, silkscreened glass - surface of the glass is imprinted with silkscreened patterns of ceramic-based paints.
frit - pigmented glass particles that are applied to glass surface and then fired in a tempering furnace, producing a hard permanent ceramic coating
spandrel glass - in glass curtain construction, the bands of glass covering the spandrel areas (the bands of wall around the edges of floors)
visible light transmittance (VT) - a measure of the transparency of glass to visible light. Clear glass has a VT in the rance of .80 to .90 or 80-90% of the visible light striking the glass passes through.
tinted glass - visible light transmittance is reduced in tinted glass from .75 in the lightest tints to .10 for dark gray
solar heat gain coefficient (SHGC) - the effectiveness of glass in reducing heat gain from solar radiation
shading coefficient - an older measure of reduction in solar hear gain mostly replaced by SHGC.
light to solar gain (LSG) ratio - a measure of the overall energy-conserving potential of glass, defined as the visible light transmittance divided by the solar heat gain coefficient.
reflective coated glass, solar control glass - thin, durable films of metal or metal oxide are deposited on the surface of either clear or tinted glass sheeds under closely controlled conditions to make reflective coated glass or solar control glass0
insulating glass unit (IGU) - An insulating glass unit commonly consists of two (sometimes more) panes of glass separated by a spacer material and sealed together at the edge. The insulating air space is filled with air or a noble gas, such as argon or krypton inside. Each glass pane has two surfaces, so typical double-paned IGUs have four surfaces. The surfaces are numbered 1 for exterior pane and increase by 1 for each inward surfaces.
U-Factor - the performance of glazing as a thermal insulator is quantified as U-factor, expressed as BTUs per square foot-hour-degree Fahrenheit. Lower values represent improved thermal performance
vacuum insulated glazing unit - a unit in which two or three glass sheets are separated by a vacuum or gas filled space to reduce heat transfer
low-emissivity coating, low-e coating - the thermal performance of glazing is improved substantially by the use of glass with a low-emissivity (low-e) coating
self-cleaning glass - coated with titanium oxide on its exterior surface enabling the coating to convert organic particles to carbon dioxide and water. It also causes rainwater to run down sheets rather than bead up. The coating is only applied to the outside of glass
chromogenic glass - glass that can change its optical properties
thermochromic glass - becomes darker when warmed by the sun
photochromic glass - becomes darker when exposed to bright light
electrochromic glass, switchable glass - changes its transparency in response to the passage of electric current
gasochromic glass - another switchable technology in which a reactive coating on the number 2 surface of an UGU is altered by pumping gas into or out of the interstitial space of the unit.
mirror glass - has a thin silverbased coating on its backside.
patterned glass - hot glass rolled into sheets with many different surface patterns and textures. It is used where light transmission is desired but vision must be obscured for privacy
radiation-shielding glass - glass manufactured with a high percentage of lead oxide
photovoltaic glass - coated with a thin film of amorphous silicon that generates electricity
aerogel - a silicon-based foam that is more than 99 percent air and is used to fill the cavity in double glazed or plastic products.Aerogel is milky in color and has a visible transmittance that varies with its thickness. Aerogel-filled glazing has a good light-to-solar-gain ratio making it an efficient source of diffuse, low-contrast, natural daylight.
glazier's point - a small, pointed piece of sheet metal, for holding a pane of glass in a sash until the putty has hardened.
glazing putty - a simple compound of linseed oil and pigment that gradually hardens by oxidation of the oil
glazing compound - improved , more adhesive, and more elastic putties employed for factory-glazed sashes
setting block - a block of synthetic rubber placed in the bottom of the frame to support the weight of the glass, normally two per lite, located at the quarter points of the bottom edge of the lite.
bite - the depth of grip on the edge of the glass provided by the supporting mullions
wet glazing component - mastic sealant of various formulations0
dry glazing component - rubber or elastomeric gaskets
preformed solid tape sealant - a thick ribbon of very sticky sealant that is adhered by pressure to the glass and mullions. The tape sealant material exerts an extremely strong hold on the glass and stays plastic indefinitely to allow for movement in the glasing system.
wedge gasket, roll-in gasket - strips of elastomeric material that are simply pushed into the gap between the glass and the mullion on teh interior side to wedge the assemnbly tightly together and seal against air leakage
lockstrip gasket - a completely self-contained glazing system.
weep hole - a hole provided in glazing assembly to drain water from the horizontal mullions to the exterior of the window frame
butt-joint glazing - the head and sill of the glass sheets aare supported conventionally in metal frames, vertical mullions are eliminated and repladced by the injection of a colorless silicone sealant
structural glazing - metal mullions lie entirely inside the glass, with the glass adhered to the mullions with structural silicone sealant or acrylic form structural glazing tape. Structural glazing allows the outside skin of the building to be completely flush, unbroken by protruding mullions
The above system assembly is used to construct multistory glass walls with no metal exposed on the exterior of the building.
suspended glazing system, glass mullion system - temperered glass sheets are suspended from above on special clamps and are stabilized against wind pressure by perpendicular stiffeners called "fins"
single-hung/double-hung window - have one ot two moving sashes which are the frames in which the glass in mounted.
Basic window nomenclature follows a tradition that has developed over many centuries. The jamb consists of the head jamb across the top of the window and the side jamb to either side. In practice, the head jamb is usually referred to simply as the head and the side jambs as jambs. The sill frames the bottom of the opening on the exterior side, and the stool does the same on the interior. Interior casings and exterior casings cover the gaps between the jambs and the rough opening, and aprons do the same below the sill and stool.
projected window - a category that includes principally casement, awning, hopper, inswinging, and pivot windows
French, Sliding, and Terrace Doors - these large glass doors most often supplied by window manufacturers,may slide in tracks or open on hinges,
wood window - being subject to the dwindling supply of knot free wood, composite wood products are increasingly used and include lumber made of short lengths of defect-free wood finger jointed and glued together, oriented strand lumber, and laminated veneer lumber. Although funcitonaly satisfactory, these materials are not attractive and are covered with wood veneer on the interior and clad with plastic or aluminum on the exterior, yielding clad wood windows.
aluminum window - The details of this commercial-grade double-hung aluminum window are keyed to the numbers on the small elevation view below. Cast and debridged thermal breaks, which are shown on the drawings as small white areas gripped by a "claw" configuration of aluminum on either side, separate the outdoor and indoor portions of all the sash and frame extrusions. Pile weatherstripping seals against air leaks at all the interfaces between sashes and frame.
plastic window frames - Though relatively new, now account for more than half of the residential market. The disadvantages of plastics are that they are not as stiff or strong as other window materials and they have very high coefficients of thermal expansion.
Following is a comparison of the coefficients of thermal expansion of wood, glass-fiber-reinforced plastic (GFRP), aluminum, and vinyl. Vinyl expands 15 times as much as wood, 8 times as much as GFRP, and 3 times as much as aluminum. Units on the graph are in./in./°F x 10-6 on the left of the vertical axis and mm/mm/°C x 10-6 on the right.
glass-fiber-reinforced plastic (GFRP) windows - frequently referred to as fiberglass windows, produced by a process called pultrusion. Relatively low in thermal expansion and like PVC, a good thermal insulator.
plastic - loosely defined as giant molecules (polymers or copolymers) made up of large numbers of small, repetitive chemical units.
synthetic rubber, elastomer - classified selarately from plastics, although chemically similar, often referred to as elastomers
polymer - a substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together
monomer - a molecule that can be bonded to other identical molecules to form a polymer
copolymer - a polymer made by reaction of two different monomers, with units of more than one kind.
thermoplastic - denoting substances (especially synthetic resins) that become plastic on heating and harden on cooling and are able to repeat these processes.
thermosetting - denoting substances (especially synthetic resins) that set permanently when heated.
crosslinked - A cross-link is a bond that links one polymer chain to another.
plasticizer - a substance (typically a solvent) added to a synthetic resin to produce or promote plasticity and flexibility and to reduce brittleness
stabilizer - a substance that prevents the breakdown of emulsions
filler - nonreacting material such as talc or marble dust
extender - waxes or oils that add bulk to the plastic at low cost
reinforcing (fibers) - fibers of glass, metal, carbon, or minerals can increase strength, impact resistance, stiffness, abrasion resistance, hardness and other properties.
The chief advantage of steel as a frame material for windows is its strength which permits steel sash sections to be slenderer than those of wood and aluminum.
Steel windows may be made of steel coated in teh factoy with a long lasting paint coating, galvanized steel or stainless steel, depending on durability and appearance requirements. Bronze windows are made in configuration similar to those for steel, usually with a patina finish.
Steel and bronze are both less conducive of heat than aluminum, so windows made of these metals are less prone to forming condensation in cold weather. Where improved thermal performance is required, thermal break systems are also available.
muntin - a bar or rigid supporting strip between adjacent panes of glass. Because of the difficulty of manufacturing large shets of glass free of significant defects, windows were necessarily divided into small lites by muntins.
six over six - a typical double-hung window had its upper sash and lower sash each divided into six lites and was referred to as a six over six.
Comparative U-Factors for various window frame and glazing combinations are displayed in the accompanying exhibit.
Lower values correspond to better thermal performance. Note that frame material has a significant impact on the performance of the overall window assembly.
Very high performance windows, with even lower overall U-factors (approximately 0.1 Btu/ft2- hr-0F or 0.6 W /m2-°K) are available from some manufacturers.
Doors fall into two general categories, exterior and interior, and offer various modes of operation.
Z-brace door - primitive doors made of planks and z-bracing were once common
stile-and-rail door - in more finished buildings, stile-and-rail doors gave a more sophisticated appearance..
flush door - in recent years, stile-and-rail doors have continued to be popular in higher-quality buildings. However, flush doors have captured the majority of the market, chiefly because they are easier to manufacture and therefore less costly.
solid core door - Solid core doors are solid from front to back. Made from wood byproducts, solid core doors are dense, heavy and withstand more punishment than hollow core doors. The typical solid core door is a mixture of wood particles glued together with heat, resins and hydraulic pressure to produce a uniform, consistent product.
hollow-core door - consists of two veneered wood faces that are nonded to a concealed frid of interior spacers made of paper-board or wood. The perimeters of the faces are glued to wood edge strips.
mineral core door - FireDefender® Mineral Core material fills most of the space in the interior of a door. It is relatively light in density at approximately 32 pounds per cubic foot. It has excellent thermal properties and through-bolting is allowed, but it is not intended to provide screw-holding capabilities. FireDefender® mineral cores are made of a proprietary mix of various minerals, fiberglass, and inert binders.
sheet metal door - Usually embossed to resemble wood stile-and-rail doors, the core is filled with insulating plastic foam making their thermal performance superior to wood doors. They do not sufer from moisture expansion and contraction as wood doors do.
GFRP door - GFRP,Glass Fiber Reinforced is another common name for Fiberglas.
Gravity - Momentum - Surface Tension - Capillary Action - Wind Currents - One approach to providing an exterior wall with water resistance is to eliminate or neutralize these five forces that can move water through the wall
gravity - Gravity is a factor in pulling water through a wall only if the wall contains an inclined plane that slopes into, rather than out of, the building. lt is usually a simple matter to detail the exterior wall system so that no such inclined planes exist, though sometimes a loose gasket or an errant bead of sealant can create one despite the best efforts of the designer.
momentum - The momentum of falling raindrops can drive water through a wall only if there is a suitably oriented slot or hole that goes completely through the wall. Momentum is neutralized by applying a cover to each joint in the wall or by designing each joint as a labyrinth.
surface tension - The surface tension of water, which causes it to adhere to the underside of a cladding component, allows water to be drawn into the building. A drip on any underside surface to which water might adhere eliminates the problem.
capillary action - Capillary action is the surface tension effect that pulls water through any opening that can be bridged by a water drop. lt is, for example, the primary force that transports water through the pores of a masonry wall. lt can be eliminated as a factor in the entry of water through a wall by making each of the openings in a wall wider than a drop of water can bridge or, if this is not feasible or desirable, by providing a concealed capillary break somewhere inside the opening. In porous materials such as brick, capillary action can be counteracted by applying an invisible water-repellent coating that destroys the adhesive force between water and the walls of the pores in the brick.
wind currents - The solutions described in the four preceding paragraphs are easy to implement. With relatively straightforward geometric manipulations of the joint, the possibility of leakage caused by four of the five forces that can move water through an opening in a wall can be eliminated. The fifth force, wind pressure, is the most difficult to deal with in designing a wall for watertightness. We can neutralize it by employing pressure-equalized wall design.
pressure-equalized wall design - 0
rainscreen - A rainscreen is an exterior wall system where the siding (wall cladding) stands off from the moisture-resistant surface of an air barrier applied to the sheathing (sheeting) to create a capillary break and to allow drainage and evaporation
rainscreen cladding, drained and back-ventilated cladding - an exterior wall system where the siding (wall cladding) stands off from the moisture-resistant surface of an air barrier applied to the sheathing (sheeting) to create a capillary break and to allow drainage and evaporation
gunnable joint sealant - viscous sticky liquids that are injected into the joints of a building with a sealant gun. They cure within the joint to become rubberlike materials that adhere to the surrounding surfaces and seal the joint against the passage of air and water.
low-range sealant, caulk - caulk with very limited elongation up to + or - 5%
elongation - stretching and squeezing capabilities of the caulk expressed as a percentage of the width of the joint
medium-range sealant - sealants such as butyl rubber or acrylic with elongation capacity in the range of + or - 5 to 10 %
high-range sealant - can safely sustain elongations up to + or - 50 to 100% and include polysulfides, polyurethanes, and silicones.
polysulfide sealant - cures by a two-component reaction
polyurethane sealant - cures by a two-component reaction or by reacting with moisture vapor from the air
silicone sealant - cures by reacting with moisture vapor from the air
sealant Type - Type S-single component, no jobsite mixing. Type M-multicomponent, jobsite mixing reqd.
sealant Grade - Grade P-pourable, self leveling Grade NS-nonsag, for vertical wall joints
sealant Class - Class 25-can tolerate 25 % expansion and contraction Class 100/50 can tolerate 100 % expansion and 50% contraction
sealant Use - Use T-traffic, can tolerate wear and physical abuse of pedestrian or vehicular traffic Use NT-nontraffic, not suitable for traffic exposure and is intended for use in vertical wall joints Use I-immersible, suitabl for sealing applications that will be submerged
gasket - strips of fully cured elastomeric(rubberlike) materials manufactured in different configurations and sizes for different sealing purposes, most commonly dry glazing
preformed cellular tape sealant - strip of polyurethane sponge material impregnated with a mastic sealant
preformed solid tape sealant - used in nonmoving lapjoints as in mounting glass in a metal frame or overlapping two sheets of metal cladding
backer rod, backup rod - a cylindrical strip of cpompressible , flexibl plastic foam just a bit larger in diameter than the width of the joint. It is pushed into the joint and held there by friction. The backer rod limits the depth to which the sealant will penetrate and maintains the optimum proportions of teh sealant bead.
loadbearing wall - Until the late 18th century nearly all large buildings were built with loadbearing exterior walls. The load bearing has been brought up to date with higher strength masonry and concrete; components such as thermal insulating materials, cavities, flashings, air barriers, and vapor retarders make the wall more resistant to the passage of water, air and heat; and the addition of steel reinforcing has allowed the wall to become thinner, lighter and better able to resist wind and seismic loads.
curtain wall - an exterior wall supported at each story by the frame. It's principal advantage is that because it bears no vertical load, it can be thin and lightweight regardless of the height of the building.
Air pressure differences can be created by (a) wind acting on external surfaces of a building, by (b) stack effect, and by (c) building mechanical equipment. Outside air infiltration increases building energy consumption, introduces air pollutants, transports water vapor into insulated walls and roofs, and it disrupts pressure differentials maintained by HVAC systems.
stack effect - the tendency of tall buildings to act as chimneys, drawing air in at either the top or bottom and expelling it at the other end
Air barrier materials control air leaks through building assemblies. To function as an air barrier, a material must be resistant to the passsage of air; it must have sufficient rigidity to withstand the air pressure differentials that act upon it; where it spans joints, it must be sufficiently resilient to accommodate movement without failure; and it must be durable enough to perform its funcion throughout the life of the building.
air barrier materials - building wraps, gypsum wallboard, polyethylene sheet plastic, rigid foam insulation, liquid-applied membranes of various formulations, flashings, sealants, gaskets, tapes.
air permeance - the measure of a materials resistance to the passage of air. The lower a materials air permeance, the better its performance as an air barrier and it is expressed as as a volume of airpassing through a standard area of material in a 1-minute period at a prescribed air pressure.
Air permeance standards for the performance of materials used in combination, or air barrier assembly, are less sstringent than those for individual materials themselves.
Recommendations for maximum air permeance of air barrier assemblies nare in the range of 0.01 to 0.04 cfm/sf @ 1.57 psf (0.05 to 0.2 L/s-m2 @ 75 Pa).
air barrier assembly - the collection of all materials responsible for the performance of a wall, roof or floor.
air barrier system - a system comprised of air barrier assemblies capable of resisting air pressure differentials acting anywhere across the heated and cooled boundary of the building.
wind washing - Wind-washing describes the problem that occurs when wind-driven air moves through walls and attic insulation, stripping its heat and lowering its R-Value.
firestopping - the process of closing off any vertical passages in the wall that are more than one story in height.
safing - a high temperature fire resistant mineral batt material that is inserted between a curtain wall panel and rthe edge of the floor slab to block the passage of fire from one floor to the next.
(a) Before the concrete frame of the building was cast, inserts were put into the formwork to form attachments for the brick veneer, including wedge anchors along the line of each shelf angle, two vertical dovetail slots in each coJumn, short vertical dovetail slots in the spandrel beams, and horizontal reglets in the centers of the spandrel beams to accept the inner edge of a flashing over each window head.
To begin installation of the brick veneer, a steel shelf angle is bolted to the spandrel beam, using malleable iron wedge inserts. A slab of polystyrene foam or mineral wool board thermal insulation (gray) is placed over the upright leg of the shelf angle, and a continuous flashing (white) is installed over the shelf angle, the insulation, and the edge of the floor slab. This flashing also wraps around the front of the column. All the seams in the flashing are overlapped and made watertight with sealant.
The first course of brickwork is laid directly on ihe shelf angle and flashing, without a bed joint of mortar. Every third head joint is left open in this first course to form a weep hole. Three courses of brickwork bring the veneer up to the level of the floor slab.
(b) The first course of the concrete masonry backup wall is laid. Vertical reinforcing bars are grouted into the hollow cores of the backup wall at intervals specified by the structural engineer. A liquid coating of adhered sheet is applied to the backup wall to act as an air and moisture barrier.
- Three more courses of brick veneer bring the top of the veneer up to the level of the top of the first course of concrete masonry. Additional insulation is placed against the concrete masonry.
- A combination joint reinforcing and masonry tie made of heavy stainless steel wires is laid on top of the masonry, tying the brick veneer to the backup wall. Plastic clips are snapped onto the tie rods of the joint reinforcing to hold the insulation in position.
- A vertical expansion joint in the brick veneer is provided at the centerline of each column. A heavy wire masonry tie in a dovetail slot anchors the brick veneer to the column on each side of the joint; another such anchor is lying loose on top of the bricks, ready to be installed, in this view.
(c) The wall rises in vertical increments of 16 inches (400 mm), which equals six courses of brick or two of concrete masonry. This is also the vertical distance between ties and the height of the insulating panels.
- A-blocks are utilized as needed in the backup wall to avoid having to thread blocks over the tops of the vertical reinforcing bars.
- The vertical expansion joint is sealed with backer rod and sealant. As an alternative to the sequence of operations illustrated here, the backup wall and air barrier may be installed to their full height first, followed later by the installation of insulation and veneer.
grid-system-supported stone cladding - A subframe of vertical steel struts supports a facing of stone panels by means of horizontal metal clips that engage slots in the upper and lower edges of the panels. To avoid corrosion and staining problems, the steel struts should be galvanized, and the clips should be made of a nonferrous metal (aluminum or stainless steel) that is chemically compatible with the type of stone being used.
(On the right) A detail of the support-to-panel connection.
(a) Parapet and (b) spandrel details for a stone panel curtain wall made of limestone, marble, or granite. The broken lines indicate the outline of the interior finish and thermal insulation components, which are not shown. Each support plate holds edges of two adjacent wall panels, which are pocketed as shown to rest on the plate. The plate should be made of a noncorroding metal. The verticaljoints between panels are closed with a backer rod and sealant.
In truss-supported stone cladding, sheets of stone are combined into ]arge pre-fabricated panels by mounting them on steel trusses. Each truss is designed to carry both wind loads and the dead load of the stone to connection brackets that transfer these loads to the frame of the building. Sealant joints and a nonstructural backup wall finish the installation.
Thicker blocks of Indiana limestone may be posttensioned together to make spandrel panels that span from column to Column but require little steel. The posttensioning tendon is threaded through matching hools that are drilled in the individual stones prior to assembly.
A Precast concrete curtain wall on a sitecast concrete frame. Panels in this example are a füll story high, each containing a fixed window. The reinforcing has been omitted from the panel for the sake of clarity, and the outline of the thermal insulation and interior finishes, which are not shown, is indicated by the broken lines.
Fabrication of a glass-fiber-reinforced concrete (GFRC) cladding panel
(a) Concrete and chopped glass fibers are sprayed into a mold and compacted with a hand roller to create a panel facing. Only the top half of the facing has been applied to the mold in this illustration.
(b) A welded frame of steel studs with L-shaped steel rod anchors is lowered onto the back of the facing and held just above it by spacers. Pads of GFRC are placed over the anchors by hand to join the facing to the frame.
(c) After overnight curing, the completed panel is removed from the mold and stored for further curing before installation.(d) Typical connections of GFRC panels to a steel building frame. The lower connection in each case is a threaded rod that can flex as necessary as the height of the upper connection is adjusted with shims.
exterior insulation and finish system (EIFS) - consists of a layer of plastic foam insulation that is adhered or mechanically fastened to a backup substrate, a reinforcing mesh that is applied to the outer surface of the form by embedment in a base coat of a stuccolike material, and an exterior finish coat of a similar material the is troweled over the reinforced base coat.
polymer-based EIFS, Class PB EIFS - uses low-density expanded polystyrene bead foam insulation,a gl;ass fiber reinforcing mesh embedded in a base coat that is formulated primarily from either portland cement or acrylic polymer, and a finish coat consisting of texture granules in an acrylic polymer vehicle
polymer-modified EIFS, Class PM EIFS, hard coat EIFS - uses a higher density, extruded polystyrene foam insulation rather than expanded bead foam. The foam panels are mechanically attached to the backup wall with metal or plastic screws. A metal reinforcing mesh is embedded in a relatively thick portland cement base coat and the finish coat is formulated of portland cement with acrylic modifiers.
barrier-wall EIFS - One of two design approachs to the control of moisture penetration in EIFS, it relies solely on the coating layers and joint sealants betweenpanels to protect against water penetration.
drainage-wall EIFS, water-managed EIFS - One of two design approachs to the control of moisture penetration in EIFS, it creates a drainage ploane between the insulation and substrate to which it is attached, allowing water that does penetrate to flow downward and back out through weeps provided at the base of each panel.
thermal break - internal components of insulating material that isolate the aluminum on the interior side of the component from aluminum on the exterior side
debridging - the process of creating a separation, or thermal break, between the inner and outer surfaces of an aluminum frame in order to reduce its thermal conductivity
cast and debridged thermal break - molten plastic is poured into a deep channel in the centre of an aluminum member where it hardens. Then aluminum that forms the bottom of the channel is cut away in a debridging process that leaves only the plastic to connect the two halves of the member.
Following is a thermally broken aluminum mullion extrusion sitting on a block of dry ice in a humid room. Frost has formed on the portion of the mullion nearest the dry ice, but the thermal break keeps the rest of the mullion warm enough that moisture does not condense on it.
polyamide strip thermal break - created with preformed polyamide thermal strips that are mechanically inserted into aluminum extrusion during extrusion manufacture. The hollow space between the strips is filled with insulation material. This thermal break is more thermally efficient than cast and debridged breaks.
anodizing - a manufacturing process that produces an integral oxide coating on alumunum that is thousands of times thicker and more durable than the natuyral oxide film that would otherwise form.
fluoropolymer coatings - are based on highly inert synthetic resins, such as polyvinylidene fluoride (PVDF) , which are exceptioinally colorfast and resistant to all forms of weathering, including ultraviolet deterioration.
powder coating - manufactured from thermosetting powders that are composed of plastic resins, such as polyester, and pigments. The powder is electrically charged and then sprayed ontothe aluminum component, which is grounded so that the powder adheres to it electrostatically. The component is then passed through an oven.
storefront - similar in appearance to curtain wall systems yet they are based on lighter framing elements that are less expensive and quicker to assemble. Most span no nore than 10-12 feet. Rather than being hung off face of building, it is installed betweenfloor slabs or within wall openings. Because of the use of lighter framing elements and simplified internal construction are limited in their ability to resist wind loads and water penetration. Therefore not used more than three or four stories high.
window wall - like the storefront, they span between the top of one slab to the underside of the next, but like a curtain wall they have internal water management features making them suitable for useon tall buildings with exposure to higher wind pressures. Accommodate a variety of operable window types. Flexible installation in that they need not be installed from bottom to top.
curtain wall - most high-performance, sophisticated, and costly of the aluminum and glass framing systems Can be applied to any number of stories..Use stronger, stiffer alum sections and resist higher wind pressures…join and attach methods tolerate movement from structural deflections and thermal expansion and contraction…sophisticated internal construction and sealing systems and water drainage
stick system - principal components are metal mullions and rectangular panels of glass and spandrel material assembled at the building. Advantages - low shipping bulk and high degree of adjustability. Typically used for entrances and storefronts
unit system, unitized system - similar benefits of stick system but requires more space during shipping and more protection from damage.
unit-and-mullion system - seldon used today, offers a middleground between stick and unit system
panel system - madeup of homogenous units formed from metal sheet. Advantages and disadvantages similar to unit system but higher production costs due to additional tooling and die costs.
column-cover-and-spandrel system - emphasizes the structural module of the building rather than create its own grid. Custom design must be created for each project..special care required in designing panel supports so as not to deflect when loads are applied to spandrel beams of building causing deformed mullions and cracked glass
outside glazed - requires that glass be installed or replaced by working from scaffolding or staging on the outside of the building. Outside glazing systems utilize simpler, less expensive shapes but are usually reserved for buildings only up to three stories.
inside glazed - allows glass installation to be performed from the inside, is more convenient and economical for a tall uilding, but requires a somewhat more elaborate set of extrusions.
The Kawneer 1600 System1® is an outside glazed stick system. Vertical mullions that run continuously from floor to floor support discontinuous horizontal mullions that are connected to them by means of shear blocks and screws.
Each lite of glass sits on two rubber glazing blocks in the gutter of the horizontal mullion (not shown in this drawing). The inner surface of the glass rests against extruded rubber glazing gaskets pressed into small channels in both the vertical and horizontal mullions.
Extruded aluminum pressure plates with rubber glazing gaskets are applied to both horizontal and vertical mullions to clamp the glass into place and create a weathertight seal.
Each pressure plate is attached by means of screws that pass through drilled holes into an extruded screw slot. A thick rubber gasket in the screw slot acts as a thermal break. Snap-on covers conceal the screw heads and give a neat exterior appearance.
A molded rubber plug at either end of each horizontal mullion contains any leakage or condensate within the horizontal mullion, from which it escapes via 5/16-inch diameter (8-mm) weep holes (not shown here) drilled through the pressure plate and the bottom edge of the snap-on cover.
In this full-size detail of the vertical mullion for the Kawneer 1600 System 1, we see that the basic extrusion is a rectangular box shape that is structurally stiff and presents a neat appearance inside the building. The broken lines indicate a smaller box mullion (162-002) that may be used for buildings with shorter floor-to-floor heights or smaller wind loads. The extruded plastic thermal break attaches to the mullion with a projecting "pine tree" spline that is pushed into the screw slot. Holes are drilled through the thermal break for the screws (not shown) that attach the pressure plate. The four rubber glazing gaskets attach to the aluminum pieces with projecting splines.
Two different horizontal mullion extrusions are available for the Kawneer 1600 System 1.
The closed extrusion (top) is used in most situations.
The open-back extrusion ( bottom) allows access to the shear block on the vertical mullion for purposes of assembly; it is used for portions of the wall that butt against other materials, such as heads, sills, and end bays.
A snap-on cover closes the open back of the mullion, leaving only a virtually invisible seam.
Rubber setting blocks are shown beneath the edges of the glass in both mullions.
In the upper-left corner of the upper detail, a small aluminum extrusion has been added to allow the mullion to hold a single layer of spandrel glass or vision glass rather than the standard 1-inch (25-mm) double-glazing assembly.
Weep holes are not shown; they are drilled horizontally through the pressure plate just above the thermal break and vertically through the bottom edge of the outside snap-on cover.
Sound Transmission Class (STC) - a measure of a materials ability to reduce the passage of sound between rooms, as outlined in ASTM E90
Impact Isolation Class (IIC) - a measure of a materials ability to reduce the transmission of impact noise from footsteps and machinery through floor-ceiling assemblies, as outlined in ASTM E492
Interior finish materials can affect:
– Noise levels
– Quality of listening conditions
– Levels of acoustic privacy
Steiner Tunnel Test - a test of the burning characteristics of interior wall and ceiling finish materials in accordance with ASTM E84
flame-spread rating - As measured by the Steiner Tunnel Test, the rapidity with which fire will spread across a surface of a given material, as outlined in ASTM E84
smoke-developed rating - As measured by the Steiner Tunnel Test, the amount of smoke a material gives off when it burns, as outlined in ASTM E84.
room fire-growth contribution - a measure of the rate at which flames are able to spread and grow, in accordance with NFPA 265
minimum critical radiant flux exposure - a measure of the combustability of flooring materials used in adjacent spaces such as exits and corridors, in accordance with NFPA 253. The purpose of the test is to ensure that flooring in essential parts of the egress system cannot be easily ignited by the radiant heat of fire and hot gases in adjacent areas.
pill test - evaluates a material's propensity for flame spread when exposed to a burning tablet intended to simulate a dropped lit cigarette
fire resistance - the ability of a wall, ceiling, or floor assembly to resist the passage of fire from one side of the assembly to the other, or pass-through resistance..
fire resistance rating - the duration for which a passive fire protection system can withstand a standardfire resistance test.
separated occupancy - The separated occupancy provisions require physical separation by fire barrier walls and/or horizontal assemblies with a fire-resistance rating between occupancies. Occupancies are located in separate fire areas, and each fire area is required to comply with the code based on the occupancy classification of that portion of the building.
nonseparated occupancy - The nonseparated occupancy provisions allow multiple occupancies without a physical separation between them. Occupancies are individually classified in accordance with IBC Chapter 3 but are not subject to the 10% area limit applicable to accessory occupancies. Fire protection systems, are applied to the total nonseparated occupancy fire area.
hose stream test - tests material's ability to resist the passage of water from a calibrated fire nozzle after being subjected to half of its rated fire exposure.
fireblocking - The fundamental principle behind Fireblock is to essentially stop fire or hot gasses that could cause a fire. It differs from firestopping in that fireblocking uses combustible materials and firestopping uses non-combustible materials to seal openings through which fire would otherwise pass.
draftstopping - prevent the movement of smoke and gasses through concealed spaces. Primarily addresses horizontal movementGoverned by code requirements:
first cost - the installed cost of interior finish systems
life-cycle cost - the total of first costs plus costs over the expected lifetime of the interior finish system such maintenance costs, fuel costs, replacement costs, and includes an assumed rate of inflation and time value of money.
fire wall - a wall that forms a required separation to restrict the spread of fire through a building and extends continuously from the foundation to or through the roof.
shaft wall - used to enclose vertical openings that extend through multiple floors of a building such as for elevators exit stairs or vertical runs of ductwork conduits or pipes
fire barrier - must extend vertically from the top of one floor slab to the underside of the next.
fire partition - less stringent than fire barriers and may terminate at the underside of a suspended ceiling for example.
smoke barrier - divides floors in such a way that occupants may take refuge in case of fire by moving to the side of the smoke barrier that is away from the fire, without having to exit the building.
smoke partition - wall constructed like a smoke barrier to resist the passage of smoke but without any fire resistance rating
furring strip - thin strips of wood or other material to level or raise surfaces of another material to prevent dampness, to make space for insulation, or to level and resurface ceilings or walls
Z-furring channel - Z-furring is used to furr out interior masonry or poured concrete wall substrates and uses z-channel furring to support rigid polystyrene, mineral, or fiberglass batt insulation
hat channel - hat-shaped corrosion-resistant framing component used to furr out masonry walls and ceiling assemblies.
adjustable - A furred gypsum board finish using adjustable furring brackets.
plaster - a generic term referring to any of a number of cement like substances that are applied to a surface in paste form and then harden into a solid material.
lath - a thin flat strip of wood, especially one of a series forming a foundation for the plaster of a wall or the tiles of a roof, or made into a trellis or fence.
wattle and daub - an early construction pastering method in which wattle, a mesh of woven sticks and vines, was covered by daub, mud plaster.
gypsum - a crystalline hydrous calcium mineral
calcining - the process of driving off water during the processing of gypsum
calcined gypsum - resultant gypsum material post hydration
plaster of Paris - calcined gypsum ground to a find powder
gypsum plasters - two types, base-coat and finish-coat with the latter differing from the addition of lime to provide additional workability and finishing qualities.
synthetic gypsum - material recovered from power plant flue gases and used in the manufacture of gypsum materials
portland cement-lime plaster - also known as stucco, it is used where plaster is likely to be subjected to moisture, as on exterior wall surfaces or in commercial kitchens and shower rooms. Exterior apps can be applied with or without sheathing. Less workable than gypsum plaster. Due to its tendency to shrink, it needs more frequent control joints.
hawk - the tool used to hold a quantity of plaster to be applied
trowel - the tool used to life the plaster from the hawk and apply the plaster to the surface and smooth in place.
darby - a straightedge that is drawn across the newly plastered surface to level it.
keying - the bonding of plaster to uneven or rough surfaces such as wood or metal lath.
lather - the skilled tradesperson who applies lath and trim accessories
expanded metal lath - thin sheete os steel that are slit and stretched in such a way as to produce a mesh of diamond-shaped openings.
Self-furring diamond mesh lath - dimples in the lath space it away from solid sheathing behind to allow plaster to key through the openings in the mesh
Paper-back lash - used for backup walls beneath ceramic tile and for exterior stucco.
Four-mesh Z-rib lath - stiffer than ordinary diamond mesh lash making it suitable for ceilings
Three-eighths-inch riblath - V-shaped ribs for exceptional rigidity, used for ceilings or concrete formwork where supports are widely spaced.
gypsum lath - 16" X 48" X 3/8" sheets of hardened gypsum plaster faced with outer layers of a special absorbent paper to protect the gypsum core. Cannot be used as a base for gypsum-lime finish plasters or portland cement stucco as they will not bond adequately to the paper facing.
ground - the term by which trim accessories are collectively known. One of their many designed purposes is to act as lines that gauge the proper thickness and plane of plaster surfaces. A straight edge can be run across them to level wet plaster.
scratch coat - The first of three coats of plaster applied over expanded metal lath.
brown coat - the second coat of plaster applied after the scratch coat has dried, intended to build strength and thickness.
plaster screeds - layers or strips of material that are leveled up to the grounds, providing reference points for setting the thickness of the plaster.
scratch coatTHe first of three coats of plaster applied over expanded metal lath. Ths coat, approx. 3/8 inch, is scratched while still wet using a notched darby to create a rough surface to which the second coat can bond mechanically.
brown coat - the second coat, approx. 3/16 inch, builds strength and thickness to present a level surface for the application of the third or finish coat.
finish coat - the third coat is a very thin application of finish-coat plaster about 1/16" thick, making the total thickness about 5/8" as measured from the face of the lath.
veneer plaster - the least expensive of the gypsum plaster systems, a plaster base is attached to the substrate with a screw-gun and then in a "double-back" process, a thin coat is followed immediately by a second "skim" coat that is finish troweled to the desired texture.
self-furring metal lath - diamond mesh lath that has a surface studded in dimples or embossed “V” groove that provides the 1/4 inch of furring required by most codes.
cast plaster ornament - made by pouring soupy plaster into molds. The plaster hardens in a few minutes, allowing the mold to be stripped and reused. Both rigid molds and soft rubber molds are used. Traditionally, rubber molds were created by first carving a plaster original, then brushing layers of latex over the original to buildup the required wall thickness, however more recently two component synthetic rubber compounds have replaced latex.
run plaster ornament - a linear ornament such as classic cornice molding. Made by the running process in which a rigid blade made of sheet metal or sheet plastic is cut to the profile of the molding. The template is then pushed back and forth along a guide strip mounted on the wall or ceiling while a mixture of lime putty and gauging plaster is inserted in front of the blade, which srikes it off to the desired profile.
gypsum board, gypsum wallboard, plasterboard, drywall - a prefabricated plaster sheet material that is manufactured in widths of 4 feet and lengths of 8 to 14 feet. "Sheetrock" is a registered trademark of one manufacturer and should not be used in a generic sense.
Type X gypsum board - required by most fire-rated assemblies, is reinforced with short glass fibers that hold the gypsum in place when exposed to fire.
Type C gypsum board - a proprietary fire-resistant alternative to type X and often a thinner board of type C may be substituted for a thicker one of type X
water-resistant gypsum backing board - include facings of water-repellent paper or glass matt
abuse or impact resisstant board - provides greater resistance to indentation and penetration and is installed where it is likely to be subjected to rough usage.
mold resistant gypaum board - combines moisture-resistant cores wit chemically treated paper or glass-matt facings that are not conducive to mold growth.
coreboard - a 1 inch thick panel that is used for shaft walls and solid gypsum board partitions, it is fabricated in sheets 24 inches wide.
ceiling gypsum board - 1/2 inch thick vs. standard 5/8" and substantially lighter yet resistant to sagging in ceiling assemblies
foil-backed gypsum board - used to eliminate the need for a separate vapor retarder in exterior wall assembly
exterior gypsum soffit board - used for exterior soffits, carport ceilings, undersides of exterior canopies and other sheltered exteior applications.
gypsum backing board - 1/4 inch gypsum board used to benefit certain sound control applications. This thickness also used for tight-radius bends.
drying-type joint compound - the most often used joint compound includes a mixture of marble dust, binder, and admixtures.
setting compound - used to minimize waiting time between applications and cure more rapidly by chemical reaction.
finish level - developed by the Gypsum Association to enable designers to specify the minimum level of finish acceptable for a project.
sound attenuation blanket - safing products that provide thermal insulation, flame resistance, and noise control. Used mainly in commercial wall systems but available for residential use as well, these blankets are made from 70% pre-consumer recycled iron-ore slag and basalt along with a phenolic resin binder, though a 90% recycled content product can also be specified.
glazed structural clay tile - used to make very durable partitions expecially in areas with heavy wear, moisture problems oro strict sanitation requirements. The ceramic glazes are non-fading and virtually indestructible.
ceramic tile facing - often added to walls for appearance, durability, sanitation, or moisture resistance
thickset tile, mortar bed tile - a tile application which is applied to a base of portland cement mortar
thin-set tile - a lower coast tile application which eliminates the mortar base and tiles are thin-set onto tile backing boards made of fiber-reinforced lightweight cement or glass-matt faced water-resistant gypsum board. Tiles are bonded to backer board most commonly with dry-set mortar, latex/polymer modified portland cement mortar, or organic adhesives.
tile backing board, backer board - Backer board is a thin layer of fiber reinforced concrete and is used under the tile to provide a firm and even surface. Due to its composition, it performs well in areas prone to humidity, such as behind shower walls and under bathroom floors.
dry-set mortar - a mix of cement, fine sand, and water retention compounds that allow the thin mortar layer to cure properly.
latex/polymer modified portland cement mortar - similar to dry-set mortar, but with additives that improve the cured mortar's freeze-thaw resistance, flexibility, and adhesion.
organic adhesive - proprietary synthetic polymer adhesives used for light-duty tile applications
tile waterproofing membrane - a membrane added to the assembly to prevent water from seeping through the tile and into the wall behind.
plenum - the space between the ceiling and the floor above
membrane ceiling - the lightweight material that stretches and clips into the track in a suspended ceiling system
membrane fire protection - a membrane ceiling can also provide fire protection when installed with appropriate material
suspended ceiling - ceilings made of almost any material such as gypsum board, plaster and various proprietary panels and tiles composed of incombustible fibers or other materials.
hanger wire - the wire attaching the ceiling framing support to the floor above.
perforated gypsum panel - panels manufactured with patterns of small holes to enhance acoustic performance
acoustical ceiling - ceiling made from fibrous materials making them absorptive of sound energy
Noise Reduction Coefficient (NRC) - the measure of the sound absorption performance of a ceiling material as a number between 0 and 1. Measure of .85 indicates 85% of sound is absorbed by ceiling material.
Ceiling Attenuation Class ( CAC) - the ability of a ceiling system to reduce sound transmissoion from one room to another through a shared plenum, measured in decibels, with higher values representing greater reductions. Closed offices with shared plenum , a CAC of not less than 35 to 40 is recommended
Articulation Class (AC) - a measure of sound reflection and absorption
lay-in panel - panels supported by an exposed grid system
exposed grid - ceiling support system with grids visible
concealed grid - ceiling support system with grids concealed wihin the lay-in panel
integrated ceiling system - systems that incorporate the lighting fixtures and air conditioning outlets into the module of the grid.
metal panel ceiling - made from sheet metal suspended in a manner similar to that for acoustical panels
linear metal ceiling - made from long metal strips suspended on a concealed grid system
suspended wood ceiling - made from solid wood or wood veneer over a variety of substrates and produced in both panel and linear forms, similar to those of metal
fabric-wrapped ceiling panel - made from natural or synthetic fabrics mounted over acoustic panels.
stretched-fabric ceiling system - made from synthetic fabric stretched across a special mounting system with acoustical insulation backing the fabric.
interstitial ceiling - a ceiling suspended at a level that allows workers to travel freely in the plenum space. Made of gypsum or lightweight concrete, they combine the construction details of poured gypsum roof decks and suspended plaster ceilings.
structureborne vibration - vibrations from impact noises generated by footsteps or machinery and transmitted through the floor material to become airborne noise in the room below
acoustic underlayment - a layer of resilient material installed beneath the finish flooring, used to reduce the amount of impact noise
static coefficient of friction (SCOF) - the coefficient of friction (COF), or slip resistance, measured starting with an object at rest.
dynamic coefficient of friction (DCOF) - the coefficient of friction (COF), or slip resistance, measured once an object has begun to slide.
static control flooring - provides a conductive pathway for the dissipation of electrical charg between occupants and equipment
cellular raceway - sheet metal ducts cast into concrete floor slabs that accommodate wires connecting communications equiment and accessed thru boxes built into raceway
cellular steel decking - in steel framed buildings, provides the same functions as cellular raceways and have poke thru fittings that extend through the floor to its underside where connections are made.
poke-through fitting - the fitting through which wiring is connected in a cellular steel decking system
raised access flooring - provides a plenum under the floor with unlimited capacity for wiring and air duct demands present and future.
undercarpet wiring system - system providing electrical power and communications via flat conductors installed between the finish flooring and the slab below.
concrete hardener - an admixture that densifies the wearing surface of concrete where additional hardness and durability are required.
paver - bricks and half-bricks used for finish flooring. They are laid in two ways, with their largest finish horizontal or on edge.
quarry tile - large fired clay tiles usually swuare but ofen rectangular, hexagonal, octagonal and other shapes.
ceramic tile - fired clay tiles smaller than quarry tiles and usually glazed
slip sheet, cleavage membrane - used where where tile is thickset over substrates that are cracked or prone to deflection. Usually consisting of builders felt, the membrane is inserted betwen mortar base and substrate to isolate the tile assembly
crack isolation membrane, uncoupling membrane - where tile is thinset over difficult substrates, this membrane preserves the necessary bond between the thinset compound and the substrate while limiting the transfer of stresses into the tile assembly.
terrazzo - an exceptionally durable flooring made by grinding and polishing concrete consisting of marble or granite chips selected for size and color in a matrix of portland cement or other binding agent.
divider strip - strips of metal plastic or marble installed in the underbed prior to pouring in order to separate the different colors. Ground and polished flush in the same operation as the terrazzo itself
sand cushion terrazzo - traditional terrazzo that is 2 1/2 inches thick and installed over a thin bed of sand that cushions it from movements in the building frame
bonded terrazzo - sand bed is eliminated
monolithic terrazzo - sand bed and underbed are eliminated
thin-set terrazzo - thinnest of all terrazzos, made from epoxy resins, polyester resins or polymer-modified cements
strip flooring - solid tongue and groove wood flooring 3/4 inch thick and 1-1/2 to 2-1/4 inches wide
blind nail - wood strips are attached by blind nail method whereby nail is driven diagonally through upper interior corners of the tongues where they are concealed from view once the next strip is installed
plank flooring - solid wood flooring in widths ranging from 3 to 8 inches
engineered wood flooring - factory made wood flooring consisting of finish wood veneers lkaminated to a plywood-like core, typically 3/8 inch or 1/2 inch thick and clued to the subfloor with mastic. Laminated structure makes it less sensitive to changes in moisture content
parquet - wood flooring of varying hues arranged in patterns
floating floor - not nailed or glued to subfloor but instead "float" on a pad of resilient foam and made by connecting individual pieces together at the edges to make one continuous piece.
plastic laminate flooring - composed of planks or large tiles that have a wood composite core and a wearing layer of high density pkastic laminate much like that used on countertops.
wood block flooring - made of small blocks of wood set in adhesive with their grain oriented vertically
resilient flooring - resilient flooring is made of materials that have some elasticity, giving the flooring a degree of flexibility called resilience and includes many different manufactured products including linoleum, sheet vinyl, vinyl composition tile (VCT), cork (sheet or tile), and rubber.
linoleum - a sheet material made of ground cork in a linseed oil binder over a burlap backing
asphalt tile - developed as an alternative to linoleum
vinyl composition tile (VCT) - made of one or more vinyl resins in combination with binders pigments and fillers(VCT may consist of as much as 85 precent limestone fillers) has the lowest installed cost of any flooring material except concrete
solid vinyl tile (SVT) - higher vinyl content and greater durability than VCT
rubber floor tile - made from vulcanized natural or synthetic rubber
resilient sheet flooring - most commonn are SVT and rubber
underlayment panel - covering for wood panel deck made of hardboard, particle board, or sanded plywood to provide smoother substrate for the resilient flooring materials. Joints between underlayment are offset from joints in subfloor to eliminate soft spots.
cove base - the base most commonly used with resilient flooring
straight base, flat base, toeless base - has no cove or toe and is most commonly used with carpet flooring
fit-to-floor base, butt-to base - has a square edged toe the same thickness as the floor covering creating a flush transition between the two
carpet - 50+ percent - nylon fibers, 35 percent - polypropylene, remainder other synthetics and natural fibers
direct glue-down installation - glue carpet directly to deck
tackless strip, tackstrip - a narrow strip of wood, attached to the floor, that has protruding spikes along the top that catch and hold carpet taut as it is stretched into place by installers
stretch-in installation - stretch carpet over carpet pad and attach to tackstrip on the perimeter
double glue-down installation - glue carpet pad to deck and then glue carpet to carpet pad
attached cushion installation - glue carpet with factory attached pad to floor
urethane floor coating, epoxy floor coating - typical application over concrete consists of preparation of the concrete surface by grinding or nlasting, application of proimer to ensure good adhesion between the substrate and the following layers, one or two coats of the primary flooring material, possibly with the addition of sand, quartz aggregate, rubber chips, or other fillers, and a top coat and/or sealer. Thickness ranges from 3/16 to 3/8 inch.
acrylic (MMA) floor coating - high in VOCs and cure in less than an hour
cementitious overlays - formulations of polymers, portland cement, fine sand, and other ingredients that are applied as self-leving fluids. Once cured they form durable polishable integrally colored, finished floor surfaces
UV-curable floor coating - emit no VOCs and cure virtually instantaneously as a machine with a controlled intensity ultraviolet lamp is rolled across wet material