Roofing Term Definitions A – C
- -A-
- Abrasion resistance
- the ability to resist being worn away by contact with another moving, abrasive surface, such as foot traffic, mechanical equipment, wind-blown particles, etc.
- Absorption
- the ability of a material to accept within its body, quantities of gases or liquid, such as moisture.
- Accelerated weathering
- the exposure of a specimen to a specified test environment for a specified time with the intent of producing in a shorter time period, effects similar to actual weathering.
- Acid etch
- in waterproofing, the use of a strong acid to remove the surface of concrete to expose the aggregate.
- Acrylic coating
- a liquid coating system based on an acrylic resin. Generally, a latex-based coating system that cures by air drying.
- Acrylic resin
- polymers of acrylic or methacrylic monomers. Often used as a latex base for coating systems.
- Active metal (anodic)
- a metal or material that readily gives up electrons to a cathodic (noble) material. (see Anodic). An active metal will corrode in the presence of moisture when in contact with a cathodic metal.
- Adhesion
- steady or firm attachment.
- Adhesive bond break
- a material to facilitate independent movement between two units that would otherwise bond together.
- Aggregate
- (1) crushed stone, crushed slag or water-worn gravel used for surfacing a built-up roof system; (2) any granular material.
- Aged R-value
- thermal resistance value established by utilizing artificial conditioning procedures for a prescribed time period.
- Air leakage
- the unintended movement of air from a location where it is intended to be contained to another location.
- Alligatoring
- the cracking of the surfacing bitumen on a bituminous roof or coating on a SPF roof, producing a pattern of cracks similar to an alligator’s hide; the cracks may not extend completely through the surfacing bitumen or coating.
- Aluminized steel
- sheet steel with a thin aluminum coating bonded to the surface to enhance weathering characteristics.
- Aluminum
- a nonrusting, malleable metal sometimes used for metal roofing and flashing.
- Anodic
- a metal or material that readily gives up electrons to a cathodic material in the presence of an electrolyte (see Galvanic Series).
- ANSI
- American National Standards Institute.
- Anticapillary hem
- a hem used in a metal panel seam to reduce the potential for water migration.
- APA
- American Plywood Association.
- APC
- American Plastics Council.
- APP
- see Atactic Polypropylene.
- Application rate
- the average quantity (mass, volume or thickness) of material applied per unit area.
- Apron flashing
- a term used for a flashing located at the juncture of the top of a sloped roof and a vertical wall, chimney or steeper-sloped roof.
- APC/SPFA
- American Plastics Council/Spray Polyurethane Foam Alliance. Architectural panel: a metal roof panel, typically a double standing seam or batten seam; usually requires solid decking underneath and relies on slope to shed water.
- Architectural shingle
- an asphalt shingle that provides a dimensional appearance.
- Area divider
- a raised, flashed assembly, typically a single- or double-wood member attached to a wood base plate, that is anchored to the roof deck. It is used to accommodate thermal stresses in a roof system where an expansion joint is not required, or to separate large roof areas or separate roof systems comprised of different/incompatible materials, and may be used to facilitate installation of tapered insulation.
- ARMA
- Asphalt Roofing Manufacturers Association.
- Area practices
- design or application techniques peculiar to a specific geographical region.
- Asbestos
- a group of natural, fibrous, impure silicate materials.
- ASHRAE
- American Society of Heating, Refrigerating and Air-Conditioning Engineers.
- Asphalt
- a dark brown or black substance found in a natural state or, more commonly, left as a residue after evaporating or otherwise processing crude oil or petroleum. Asphalt may be further refined to conform to various roofing grade specifications
- Dead-level asphalt
- a roofing asphalt conforming to the requirements of ASTM Specification D 312, Type I.
- Flat asphalt
- a roofing asphalt conforming to the requirements of ASTM Specification D 312, Type II.
- Steep asphalt
- a roofing asphalt conforming to the requirements of ASTM Specification D 312, Type III.
- Special steep asphalt
- a roofing asphalt conforming to the requirements of ASTM Specification D 312, Type IV.
- Asphalt, Air blown
- asphalt produced by blowing air through molten asphalt to raise its softening point and modify other properties.
- Asphalt emulsion
- a mixture of asphalt particles and emulsifying agent, such as bentonite clay and water.
- Asphalt felt
- an asphalt-saturated and/or asphalt-coated felt (see Felt).
- Asphalt primer
- see Primer.
- Asphalt roof cement
- a trowelable mixture of solvent-based bitumen, mineral stabilizers, other fibers and/or fillers. Classified by ASTM Standard D 2822-1 Asphalt Roof Cement, and D 4586-2 Asphalt Roof Cement, Asbestos-Free, Types I and II. Type I is sometimes referred to as “plastic cement,” and is made from asphalt characterized as self-sealing, adhesive and ductile, and conforming to ASTM Specification D 312, Type I; Specification D 449, Types I or II; or Specification D 946 (see Plastic Cement and Flashing Cement). Type II is generally referred to as “vertical-grade flashing cement,” and is made from asphalt characterized by a high softening point and relatively low ductility, and conforming to the requirement of ASTM Specification D 312, Types II or III; or Specification D 449, Type III. (see Plastic Cement and Flashing Cement).
- Asphalt shingle
- a shingle manufactured by coating a reinforcing material (felt or fibrous glass mat) with asphalt and having mineral granules on the side exposed to the weather. (see Shingle)
- Asphaltene
- a high molecular weight hydrocarbon fraction precipitated from asphalt by a designated solvent (paraffinic naphtha) at a specified temperature and solvent-asphalt ratio.
- ASTM
- American Society for Testing and Materials.
- Atactic
- polypropylene: a group of high molecular weight polymers formed by the polymerization of propylene. The NRCA Roofing and Waterproofing Manual—Fifth Edition 974 Glossary
- Attic
- the cavity or open space above the ceiling and immediately under the roof deck of a steep-sloped roof.
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- -B-
- Back-nailing (also referred to as “Blind-nailing”)
- the practice of blind nailing the back portion of a roofing ply, steep roofing unit, or other components in a manner so that the fasteners are covered by the next sequential ply, or course, and are not exposed to the weather in the finished roof system
- Ballast
- a material, such as aggregate or precast concrete pavers, which employs its mass and the force of gravity to hold (or assist in holding) single-ply roof membranes in place.
- Bar joist
- (see Steel Joist).
- Barrel vault
- a building profile featuring a rounded profile to the roof on the short axis, but with no angle change on a cut along the long axis.
- Barrier board
- noncombustible board stock material of low thermal conductivity placed between two elements of a roof assembly.
- Base flashing (membrane base flashing)
- plies or strips of roof membrane material used to close-off and/or seal a roof at the horizontal-to-vertical intersections, such as at a roof-to-wall juncture. Membrane base flashing covers the edge of the field membrane. (see Flashing).
- Base ply
- the bottom or first ply in a built-up roof membrane when additional plies are to be subsequently installed.
- Base sheet
- an impregnated, saturated, or coated felt placed as the first ply in some low-slope roof systems.
- Batten
- (1) cap or cover; (2) in a metal roof, a metal closure set over, or covering the joint between, adjacent metal panels; (3) in a wood roof, a strip of wood usually set in or over the structural deck, used to elevate and/or attach a primary roof covering such as tile; (4) in a single ply membrane roof system, a narrow plastic, wood or metal bar that is used to fasten or hold the roof membrane and/or base flashing in place.
- Batten seam
- a metal panel profile attached to and formed around a beveled wood or metal batten.
- Bentonite
- a porous clay formed by the decomposition of volcanic ash that swells 5 to 6 times its original volume in the presence of water.
- Bermuda seam
- a metal panel profile featuring a step-down profile that runs perpendicular to the slope of the roof.
- Bird bath
- random, inconsequential amounts of residual water on a roof membrane.
- Bitumen
- (1) a class of amorphous, black or dark colored, (solid, semi-solid or viscous) cementitious substances, natural or manufactured, composed principally of high molecular weight hydrocarbons, soluble in carbon disulfide, and found in asphalts, tars, pitches and asphaltenes; (2) a generic term used to denote any material composed principally of bitumen, typically asphalt or coal tar.
- Bitumen-stop
- see Envelope or Bleed-sheet.
- Bituminous emulsion
- a suspension of minute particles of bituminous material in water.
- Blackberry (also referred to as “Blueberry” or “Tar-boil”)
- a small bubble or blister in the flood coat of an aggregate-surfaced built-up roof membrane.
- Blanket (batt) insulation
- glass fiber or other compressible fibrous insulation, generally available in roll form.
- Bleed-sheet
- a sheet material used to prevent the migration of bitumen.
- Bleeder strip
- see Rake-starter.
- Blind-nailing
- the use of nails that are not exposed to the weather in the finished roofing system.
- Blister
- an enclosed pocket of air, which may be mixed with water or solvent vapor, trapped between impermeable layers of felt or membrane, or between the membrane and substrate. The NRCA Roofing and Waterproofing Manual—Fifth Edition Glossary 975
- Blocking
- sections of wood (which may be preservative treated) built into a roof assembly, usually attached above the deck and below the membrane or flashing, used to stiffen the deck around an opening, act as a stop for insulation, support a curb, or serve as a nailer for attachment of the membrane and/or flashing.
- Blowing agent
- an expanding agent used to produce a gas by chemical or thermal action, or both, in manufacture of hollow or cellular materials.
- BOCA
- Building Officials and Code Administrators, International, Inc.
- Bond
- the adhesive and/or cohesive forces holding two components in positive contact.
- Boot
- (1) a covering made of flexible material, which may be preformed to a particular shape, used to exclude dust, dirt, moisture, etc., from around a penetration; (2) a flexible material used to form a closure, sometimes installed at inside and outside corners.
- Brake
- hand- or power-activated machinery used to bend metal.
- Bridging
- (1) when membrane or base flashing is unsupported at a juncture; (2) bridging in steep-slope roofing occurs when reroofing over standard-sized asphalt shingles with metric-sized asphalt shingles.
- British thermal unit (BTU)
- the heat energy required to raise the temperature of 1 pound of water degree Fahrenheit (joule). For the metric equivalent, (see Joule.)
- Broadcast
- uniformly cast or distribute granular or aggregate surfacing material.
- Brooming
- to improve the embedding of a ply or membrane by using a broom or squeegee to smooth it out and ensure contact with the adhesive under the ply or membrane.
- Buckle
- an upward, elongated displacement of a roof membrane frequently occurring over insulation or deck joints. A buckle may be an indication of movement within the roof assembly.
- Building code
- The minimum construction requirements established generally by national organizations of experts and adopted completely or in altered form by local governing authorities.
- Built-up roof (BUR)
- a continuous, semi-flexible roof membrane, consisting of multiple plies of saturated felts, coated felts, fabrics or mats assembled in place with alternate layers of bitumen, and surfaced with mineral aggregate, bituminous materials, a liquid-applied coating or a granule-surfaced cap sheet.
- Bundle
- an individual package of shakes or shingles.
- Bun stock
- large solid box-like structure formed during the production of polystyrene insulation; individual board stock pieces are then cut from the bun.
- Butt joint
- a joint formed by adjacent, separate sections of material, such as where two neighboring pieces of insulation abut.
- a process of indenting two or more thicknesses of metal that are pressed against each other to prevent slippage between the metal.
- Butyl
- rubber-like material produced by polymerizing isobutylene.
- Butyl coating
- an elastomeric coating system derived from polymerized isobutylene. Butyl coatings are characterized by low water vapor permeability.
- Butyl rubber
- a synthetic elastomer based on isobutylene and a minor amount of isoprene. It can be vulcanized and features low permeability to gases and water vapor.
- Butyl tape
- a sealant tape sometimes used between metal roof panel seams and/or end laps; also used to seal other types of sheet metal joints, and in various sealant applications. The NRCA Roofing and Waterproofing Manual—Fifth Edition 976 Glossary
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- -C-
- Calender
- (1) to press between rollers or plates in order to smooth and glaze or to thin into sheets; (2) a machine for calendering.
- Camber
- a slight convexity, arching or curvature (as of a beam, roof deck or road).
- Canopy
- any overhanging or projecting roof structure, typically over entrances or doors.
- Cant
- in SPF-based roofing, a beveling of foam at horizontal/vertical joints to increase strength and promote water run off.
- 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.
- Cap flashing
- (1) usually composed of metal, used to cover or shield the upper edges of the membrane base flashing wall flashing; (2) a flashing used to cover the top of various buildings components, such as parapets or columns. (see Flashing and Coping.)
- Cap sheet
- a sheet, often granule-surfaced, used as the top ply of some built-up or modified bitumen roof membranes and/or flashings.
- Capacitance meter
- a device used to locate moisture or wet materials within a roof system by measuring the ratio of the change to the potential difference between two conducting elements separated by a non-conductor.
- Capillary action
- (1) the action by which the surface of a liquid where it is in contact with a solid is elevated or depressed depending on the relative attraction of the molecules of the liquid for each other and for those of the solid; (2) the siphoning of liquid into a joint or void between two adjacent surfaces.
- Catalyst
- an ingredient that initiates a chemical reaction or increases the rate of a chemical reaction when combined with another chemical.
- Cathodic
- A metal or material that readily attracts electrons from an anodic material in the presence of an electrolyte (see Galvanic Series).
- Caulk
- a composition of vehicle and pigment used at ambient temperatures for filling/sealing joints or junctures, that remains elastic for an extended period of time after application.
- Caulking
- (1) the physical process of sealing a joint or juncture; (2) sealing and making weather-tight the joints, seams or voids between adjacent surfaces by filling with a sealant.
- Cavitation
- the formation of a partial vacuum or cavity in a liquid.
- Cavity wall
- an exterior wall usually of masonry, consisting of an outer and inner withe separated by a continuous air space, but connected together by wire or sheet-metal tiles.
- C-channel
- a structural framing member.
- Cellular glass insulation
- A rigid closed-cell insulation board made from crushed glass and hydrogen sulfide gas.
- Cementitious waterproofing
- heavy cement-based compounds and various additives that are mixed and packaged for use in a dry form; the packaged mixture is then mixed with water and liquid bonding agents to a workable concrete-like consistency.
- Centipoise
- a unit of measure of absolute viscosity. (The viscosity of water is one centipoise. The lower the number, the less viscous the material.)
- Centistoke
- a unit of viscosity; the ratio of a liquid’s absolute viscosity to the density of that liquid.
- CERL
- Construction Engineering Research Laboratory.
- Chalk
- a powdery residue on the surface of a material. The NRCA Roofing and Waterproofing Manual—Fifth Edition Glossary 977
- Chalk line
- a line made on the roof or other flat surface by snapping a taut string or cord dusted with colored chalk.
- Chalking
- the formation of a powdery surface condition from the disintegration of a binder or elastomer.
- Channel flashing
- in steep-slope roof construction, a type of flashing used at roof-to-wall junctures and other rooftop-vertical plane intersections where an internal gutter is needed to handle runoff. Commonly used with profile tile.
- Chemical resistance
- the ability to withstand contact with specified chemicals without a significant change in properties.
- Chimney
- stone, masonry, prefabricated metal or wood-framed structure, containing one or more flues, projecting through and above the roof.
- Chlorinated polyethylene (CPE)
- a thermoplastic material, used for single-ply roof membranes, composed of high molecular weight polyethylene that has been chlorinated with a process that yields a flexible rubber-like material.
- Chlorosulfonated polyethylene (CSPE or CSM)
- probably best known by the DuPont trade name Hypalon™, a synthetic, rubber-like thermoset material, based on high molecular weight polyethylene with sulphonyl chloride, usually formulated to produce a self-vulcanizing membrane. Classified by ASTM Standard D 5019.
- Cladding
- a material used as the exterior wall enclosure of a building.
- Cleat
- a continuous metal strip, or angled piece, used to secure metal components (see Clip).
- Clerestory
- an upward extension of enclosed space created by carrying a setback vertical, wall (typically glazed) up and through the roof slope. Two intersecting shed roofs on different planes.
- Clip
- A non-continuous metal component or angle piece used to secure two or more metal components together. (see Cleat).
- Clipped gable
- a gable cutback near the peak in a hip-roof form.
- Closed-cut valley
- a method of valley application in which shingles from one side of the valley extend across the valley while shingles from the other side are trimmed back approximately 2 inches (51 mm) from the valley centerline.
- Closure strip
- a metal or resilient strip, such as neoprene foam, used to close openings created by joining metal panels or sheets and flashings.
- Coal tar
- a dark brown to black colored, semi-solid hydrocarbon produced by the distillation of coal. Coal tar pitch is further refined to conform to the following roofing grade specifications
- Coal tar pitch
- a coal tar used as the waterproofing agent in dead-level or low-slope built-up roof membranes and membrane waterproofing systems, conforming to ASTM Specification D 450, Type I.
- Coal tar waterproofing pitch
- a coal tar used as the dampproofing or waterproofing agent in below-grade structures, conforming to ASTM Specification D 450, Type II.
- Coal tar bitumen
- a proprietary trade name for Type III coal tar used as the dampproofing or waterproofing agent in dead-level or low-slope built-up roof membranes and membrane waterproofing systems, conforming to ASTM D 450, Type III.
- Coal tar felt
- a felt that has been saturated or impregnated with refined coal tar.
- Coal tar roof cement
- a trowelable mixture of processed coal tar base, solvents, mineral fillers and/or fibers. Classified by ASTM Standard D 4022, “Coal Tar Roof Cement, Asbestos Container.”
- Coarse orange peel surface texture
- a surface showing a texture where nodules and valleys are approximately the same size and shape. This surface is acceptable for receiving a protective coating because of the roundness of the nodules and valleys. The NRCA Roofing and Waterproofing Manual—Fifth Edition 978 Glossary
- Coated base sheet
- a coated felt intended to be used as a base ply in a built-up or modified bitumen roof membrane.
- Coated fabric
- fabrics that have been impregnated and/or coated with a plastic like material in the form of a solution, dispersion hot-melt or powder. The term also applies to materials resulting from the application of a preformed film to a fabric by means of calendering.
- Coated felt (Sheet)
- (1) an asphalt felt that has been coated on both sides with harder, more viscous asphalt; (2) a glass fiber felt that has been simultaneously impregnated and coated with asphalt on both sides.
- Coating
- a layer of liquid material applied to a surface for protection or appearance.
- Cobwebbing
- a phenomenon observed during spray application characterized by the formation of web-like threads along with the usual droplets leaving the spray gun nozzle.
- Code
- a collection of laws (regulations, ordinances or statutory requirements) adopted by governmental authority. (see Building Code and Model Code).
- Coefficient of thermal expansion
- the coefficient of change in dimension of a material per unit of dimension per degree change in temperature.
- Cohesion
- the molecular forces of attraction by which the body of a material is held together.
- Coil coating
- the application of a finish to a coil of metal using a continuous mechanical coating process.
- Cold forming
- the process of shaping metal into desired profiles without the application of heat.
- Cold rolled
- the process of forming steel into sheets, panels, or shapes on a series of rollers at room temperature.
- Cold roof assembly
- a roof assembly configured with the insulation below the deck, not typically in contact with the deck, allowing for a ventilation space. The temperature of the roof assembly remains close to the outside air temperature.
- Color stability
- the ability of a material to retain its original color after exposure to weather.
- Column
- in structures, a relatively long, slender structural compression member such as a post, pillar or strut; usually vertical which acts in (or near) the direction of its longitudinal axis.
- Combing ridge
- a term used to describe an installation of finishing slate or wood at the ridge of a roof whereby the slates on one side project beyond to the apex of the ridge.
- Combustible
- capable of burning.
- Combustion
- a chemical process of oxidation that occurs at a rate fast enough to produce heat and usually light either as glow or flames; the process of burning.
- Compatible materials
- two or more substances that can be mixed, blended, or attached without separating, reacting, or affecting the materials adversely.
- Composition shingle
- a unit of asphalt shingle roofing.
- Composite board roof insulation
- rigid board insulation generally comprised of perlite or wood fiberboard factory bonded to polyisocyanurate or polystyrene.
- Compounded thermoplastics
- a category of roofing membranes made by blending thermoplastic resins with plasticizers, various modifiers, stabilizers, flame retardants, UV absorbers, fungicides and other proprietary substances alloyed with proprietary organic polymers.
- Compressive strength
- the property of a material that relates to its ability to resist compression loads. The NRCA Roofing and Waterproofing Manual—Fifth Edition Glossary 979
- Concealed-nail method
- a method roofing application in which all nails are driven into the underlying course of roofing and covered by a subsequent, overlapping course.
- Concealed plate
- see Cover Plate.
- Condense
- to make denser or more compact, as when a material (e.g., water vapor) changes from its gas phase to its liquid phase.
- Condensate
- the liquid resulting from the condensation of a gas.
- Condensation
- the conversion of water vapor or other gas to liquid phase as the temperature drops; the act or process of condensing.
- Conditioning
- the storage of a material specimen under specified temperature, humidity, etc. for a specified time prior to testing.
- Conductance, Thermal
- the thermal transmission in unit time through unit area of a particular body or assembly having defined surfaces, when unit average temperature difference is established between the surfaces. C=Btu/h•ft2•°F (C=W/m2•K).
- Conductor head
- an enlargement or catch basin at the top of a downspout or leader to receive rainwater from a gutter or scupper.
- Construction joint
- (1) a joint where two successive placements of concrete meet; (2) a separation provided in a building which allows its component parts to move with respect to each other.
- Contact cements
- adhesives used to adhere or bond various roofing components. These adhesives adhere mated components immediately on contact of surfaces to which the adhesive has been applied.
- Contamination
- the process of making a material or surface unclean or unsuited for its intended purpose, usually by the addition or attachment of undesirable foreign substances.
- Control joint
- a groove which is formed, sawed, or tooled in a concrete or masonry structure to regulate the location and amount of cracking and separation resulting from the dimensional change of different parts of the structure, thereby avoiding the development of high stresses.
- Coping
- the covering piece on top of a wall exposed to the weather, usually made of metal, masonry, or stone and sloped to carry off water.
- Copolymer
- the product of polymerization of two or more substances (as two different isomers) together.
- Copolymerization
- a chemical reaction that results in the bonding of two or more dissimilar monomers to produce large, long-chain molecules that are copolymers.
- Copper
- a natural weathering metal used in metal roofing or flashing; typically used in 16 ounce per square foot (0.56 mm) and 20 ounce per square foot (0.69 mm) thicknesses.
- Core cut or core sample
- (1) a sample from a low-slope roof system taken for the purpose of obtaining primarily qualitative information about its construction. Typically, core cut analysis can verify or reveal the type of membrane surfacing; the type of membrane; the approximate number of plies; the type, thickness and condition of the insulation (if any); and the type of deck used as a substrate for the roof system. (2) for in SPF-based roof systems, core cuts are used to obtain both quantitative and qualitative information, such as the thickness of the foam, the thickness and adhesion of the coating, thickness of individual passes and adhesion between passes and the adhesion of the foam to its substrate.
- Cornice
- the decorative horizontal molding or projected roof overhang.
- Counter batten
- vertical wood strips installed on sloped roofs over which horizontal battens are secured. The primary roof covering is attached or secured to these horizontal battens. The NRCA Roofing and Waterproofing Manual—Fifth Edition 980 Glossary
- Counterflashing
- formed metal or elastomeric sheeting secured on or into a wall, curb, pipe, rooftop unit or other surface, to cover and protect the upper edge of a base flashing and its associated fasteners.
- Course
- (1) the term used for a row of roofing material that forms the roofing, waterproofing or flashing system; (2) one layer of a series of materials applied to a surface (e.g., a five-course wall flashing is composed of three applications of roof cement with one ply of felt or fabric sandwiched between two layers of roof cement).
- Cover board
- an insulation board used over closed cell plastic foam insulation (e.g., polyisocyanurate) to prevent blistering when used in conjunction with hot bituminous membranes. Suitable cover board insulation are glassfaced siliconized gypsum board, glass-fiber board, perlite board, wood-fiber board or mineral-fiber board. Cover boards are also recommended between polyisocyanurate insulation and single ply membranes to protect the polyisocyanurate.
- Cover plate
- a metal strip sometimes installed over or under the joint between formed metal pieces.
- Coverage
- the surface area uniformly covered by a specific quantity of a particular material at a specific thickness.
- CPA
- copolymer alloy.
- Crack
- a nonlinear separation or fracture occurring in a material.
- Cream time
- time in seconds (at a given temperature) when the A and B components of polyurethane foam will begin to expand after being mixed. Recognizable as a change in color of the materials.
- Cricket
- a relatively small area of a roof constructed to divert water from a horizontal intersection of the roof with a chimney, wall, expansion joint or other projection. (see Saddle).
- Cross-linking
- the formation of chemical bonds between polymeric chains. Cross-linking of rubber is referred to as vulcanization or “curing.”
- CRREL
- Cold Regions Research and Engineering Laboratory.
- Crystalline waterproofing
- a compound of cement, quartz or silica sand, and other active chemicals that are mixed and packaged for use in a dry powder form; the packaged mixture is then mixed with water and applied to a concrete surface where it penetrates into the pores of concrete.
- CSPE
- chlorosulfonated polyethylene.
- Cupola
- a relatively small roofed structure, generally set on the ridge or peak of a main roof area for ventilation or aesthetic purposes.
- Curb
- (1) a raised member used to support roof penetrations, such as skylights, mechanical equipment, hatches, etc. above the level of the roof surface; (2) a raised roof perimeter relatively low in height.
- Cure
- a process whereby a material is caused to form permanent molecular linkages by exposure to chemicals, heat, pressure and/or weathering.
- Cure time
- the time required for a material to reach its desirable long-term physical characteristics.
- Cured concrete
- concrete that has attained its intended design performance properties.
- Curing agent
- an additive in a coating or adhesive that results in increased chemical activity between the components with an increase or decrease in rate of cure.
- Curing compound
- a liquid that is sprayed or otherwise applied to newly placed concrete which retards the loss of water during curing.
- Cutback
- solvent-thinned bitumen used in cold-process roofing adhesives, roof cements and roof coatings. The NRCA Roofing and Waterproofing Manual—Fifth Edition Glossary 981
- Cutoff
- a permanent detail designed to prevent lateral water movement in an insulation system and used to isolate sections of a roofing system. (Note: A cutoff is different from a tie-in, which may be a temporary or permanent seal.) (see Tie-In).
- Cutout
- the open portions of a strip shingle between the tabs. Sometimes referred to as a keyway.
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