GLOSSARY APPENDIX 1

Abrasion resistance Aggregate The ability to resist being worn away by (1) Crushed stone, crushed slag, or water- contact with another moving, abrasive worn gravel used for surfacing a built-up surface, such as foot traffic, mechanical roof system; (2) Any granular material. equipment, wind-blown particles, etc. Aged R-value Absorption Thermal resistance value established by The ability of a material to accept within its utilizing artificial conditioning procedures for body quantities of gases or liquid, such as a prescribed time period. moisture. Air leakage Accelerated weathering The unintended movement of air from a The exposure of a specimen to a specified location where it is intended to be contained test environment for a specified time with to another location. the intent of producing in a shorter time period the effects similar to actual Alligatoring weathering. The cracking of the surfacing bitumen on a bituminous roof or coating on a SPF roof, Acid etch producing a pattern of cracks similar to an In waterproofing, the use of a strong acid to alligator's hide; the cracks may not extend remove the surface of concrete to expose completely through the surfacing bitumen or the aggregate. coating.

Acrylic coating Aluminized steel A liquid coating system based on an acrylic Sheet steel with a thin aluminum coating resin. Generally, a water-based coating bonded to the surface to enhance system that cures by air drying. weathering characteristics.

Acrylic resin Aluminum Polymers of acrylic or methacrylic A nonrusting, malleable metal sometimes monomers. Often used as a base for used for metal roofing and flashing. coating systems. Anodic Active metal (anodic) A metal or material that readily gives up A metal or material that readily gives up electrons to a cathodic material in the electrons to a cathodic (noble) material. presence of an electrolyte. (See Galvanic (See Anodic.) An active metal will corrode series.) in the presence of moisture when in contact with a cathodic metal. Anti-Capillary hem A hem used in a metal panel seam to Adhesion reduce the potential for water migration. Steady or firm attachment. Application rate Adhesive bond break The average quantity (mass, volume, or A material to facilitate independent thickness) of material applied per unit area. movement between two units that would otherwise bond together. Apron flashing Term used for a flashing located at the

A1-1 GLOSSARY APPENDIX 1

juncture of the top of a sloped roof and a Flat asphalt vertical wall, chimney, or steeper-sloped roof. A roofing asphalt conforming to the requirements of ASTM Specification Architectural panel D 312, Type II. A metal roof panel, typically a double standing seam or batten seam; generally Steep asphalt requires solid decking underneath and A roofing asphalt conforming to the relies on slope to shed water. Also see requirements of ASTM Specification Non-structural Panel. D 312, Type III.

Architectural shingle Special steep asphalt An asphalt shingle that provides a A roofing asphalt conforming to the dimensional appearance. (see also requirements of ASTM specification Dimensional Shingle and Laminated D312, Type IV. Shingle) Asphalt, Air blown Area divider Asphalt produced by blowing air through A raised, flashed assembly; typically a single- molten asphalt to raise its softening point or double-wood member attached to a wood and modify other properties. base plate that is anchored to the roof deck. It is used to accommodate thermal stresses in Asphalt emulsion a roof system where an expansion joint is not A mixture of asphalt particles and required, or to separate large roof areas or emulsifying agent, such as bentonite clay separate roof systems comprised of different/ and water. incompatible materials, and may be used to facilitate installation of tapered insulation. Asphalt felt An asphalt-saturated and/or asphalt-coated Area practices felt. (See Felt.) Design or application techniques peculiar to a specific geographical region. Asphalt primer See Primer. Asbestos A group of natural, fibrous impure silicate Asphalt roof cement materials. A trowelable mixture of solvent-based bitumen, mineral stabilizers, other fibers Asphalt and/or fillers. Classified by ASTM Standard A dark brown or black substance found in a D2822-1 Asphalt Roof Cement, and natural state or, more commonly, left as a D4586-2 Asphalt Roof Cement, Asbestos- residue after evaporating or otherwise Free, Types I and II. processing crude oil or petroleum. Asphalt may be further refined to conform to various Type I is sometimes referred to as "plastic roofing grade specifications: cement," and is made from asphalt characterized as self-sealing, adhesive Dead-level asphalt and ductile, and conforming to ASTM A roofing asphalt conforming to the Specification D312, Type I; Specification requirements of ASTM Specification D449, Types l or II; or Specification D946. D 312, Type I. (See Plastic cement and flashing cement.)

A1-2 GLOSSARY APPENDIX 1 Type II is generally referred to as "vertical- and the force of gravity to hold (or assist in grade flashing cement," and is made from holding) single-ply roof membranes in asphalt characterized by a high softening place. point and relatively low ductility, and conforming to the requirement of ASTM Bar joist Specification D312, Types II or III; or (See Steel joist.) Specification 0 449, Type III. (See Plastic cement and flashing cement.) Barrel vault A building profile featuring a rounded profile Asphalt shingle to the roof on the short axis, but with no A shingle manufactured by coating a angle change on a cut along the long axis. reinforcing material (felt or fibrous glass mat) with asphalt and having mineral Barrier board granules on the side exposed to the Noncombustible board stock material of low weather. (See Shingle) thermal conductivity placed between two elements of a roof assembly. Asphaltene A high molecular weight hydrocarbon fraction Base flashing (membrane base flashing) precipitated from asphalt by a designated Plies or strips of roof membrane material solvent (paraffinic naphtha) at a specified used to close-off and/or seal a roof at the temperature and solvent-asphalt ratio. horizontal-to-vertical Intersections, such as at a roof-to-wall juncture. Membrane Atactic polypropylene base flashing covers the edge of the field A group of high molecular weight polymers membrane. (See Flashing.) formed by the polymerization of propylene. Base ply Attic The bottom or first ply in a built-up roof The cavity or open space above the ceiling membrane when additional plies are to be and immediately under the roof deck of a subsequently installed. steep-sloped roof. Base sheet AZ50 An impregnated, saturated, or coated felt A popular coating thicknesses for Galvalume placed as the first ply in some low-slope Steel similar to the G90 coating used on roof systems. galvanized steel. Batten Back-nailing (also referred to as "Blind- (1) Cap or cover; (2) In a metal roof, a nailing") metal closure set over, or covering the joint The practice of blind nailing the back portion between, adjacent metal panels; (3) In a of a roofing ply, steep roofing unit or other wood roof, a strip of wood usually set in or components in a manner so that the over the structural deck, used to elevate fasteners are covered by the next sequential and/or attach a primary roof covering such ply, or course, and are not exposed to the as tile; (4) In a single ply membrane roof weather in the finished roof system. system, a narrow plastic, wood or metal bar that is used to fasten or hold the roof Ballast membrane and/or base flashing in place. A material, such as aggregate or precast concrete pavers, which employs its mass

A1-3 GLOSSARY APPENDIX 1

Batten seam Blanket (batt) insulation A metal panel profile attached to and formed Glass fiber or other compressible fibrous around a beveled wood or metal batten. insulation, generally available in roll form.

Bentonite Bleed-sheet A porous clay formed by the decomposition A sheet material used to prevent the of volcanic ash that swells 5 to 6 times its migration of bitumen. original volume in the presence of water. Bleeder strip Bermuda seam (See Rake-starter.) A metal panel profile featuring a stepdown profile that runs perpendicular to the slope of Blind-nailing the roof. The use of nails that are not exposed to the weather in the finished roofing system. Bird bath Random amounts of residual water on a Blister roof membrane. An enclosed pocket of air, which may be mixed with water or solvent vapor, trapped Bitumen between impermeable layers of felt or (1) A class of amorphous, black or dark membrane, or between the membrane colored (solid semi-solid or viscous) and substrate. cementitious substances natural or manufactured, composed principally of high Blocking molecular weight hydrocarbons, soluble in Sections of wood (which may be carbon disulfide and found in asphalts, tars, preservative treated) built into a roof pitches and asphaltenes; (2) A generic term assembly, usually attached above the deck used to denote any material composed and below the membrane or flashing, used principally of bitumen, typically asphalt or to stiffen the deck around an opening, act coal tar. as a stop for insulation, support a curb, or serve as a nailer for attachment of the Bitumen-stop membrane and/or flashing. (See Envelope or bleed-sheet.) Blowing agent Bituminous coating An expanding agent used to produce a gas A bituminous material used as a coating by chemical or thermal action, or both, in between two dissimilar materials. Typically manufacture of hollow or cellular materials. used for corrosion protection and sound reduction. Bond The adhesive and/or cohesive forces Bituminous emulsion holding two components in positive contact. A suspension of minute particles of bituminous material in water. Boot (1) A covering made of flexible material, Blackberry (also referred to as which may be preformed to a particular "Blueberry" or "Tarboil") shape, used to exclude dust, dirt, moisture, A small bubble or blister in the flood coat of etc., from around a penetration; (2) A flexible an aggregate-surfaced built-up roof material used to form a closure, sometimes membrane. installed at inside and outside corners.

A1-4 GLOSSARY APPENDIX 1

Brake granule-surfaced cap sheet. Hand- or power-activated machinery used to bend metal. Bundle An individual package of metal panels, Bridging shakes, or shingles. (1) When membrane or base flashing is unsupported at a juncture; (2) Bridging in Bun stock steep-slope roofing occurs when reroofing Large solid box-like structure formed during over standard-sized asphalt shingles with the production of polystyrene insulation; metric-sized asphalt shingles. individual board stock pieces are then cut from the bun. British thermal unit (BTU) The heat energy required to raise the Butt joint temperature of 1 pound of water degree A joint formed by adjacent, separate Fahrenheit (joule). For the metric sections of material, such as where two equivalent, see Joule. neighboring pieces of insulation abutt.

Broadcast Button punch Uniformly cast or distribute granular or A process of indenting two or more aggregate surfacing material. thicknesses of metal that are pressed against each other to prevent slippage Brooming between the metal. To improve the embedding of a ply or membrane by using a broom or squeegee Butyl to smooth it out and ensure contact with the Rubber-like material produced by adhesive under the ply or membrane. polymerizing isobutylene.

Buckle Butyl coating An upward, elongated displacement of a An elastomeric coating system derived from roof membrane frequently occurring over polymerized isobutylene. Butyl coatings are insulation or deck joints. A buckle may be characterized by low water vapor permeability. an indication of movement within the roof assembly. Butyl rubber A synthetic elastomer based on isobutylene Building code and a minor amount of isoprene. It can be The minimum construction requirements vulcanized and features low permeability to established generally by national gases and water vapor. organizations of experts and adopted completely or in altered form by local Butyl tape governing authorities. A sealant tape used between metal roof panel seams and/or end laps; also used to Built-up roof (BUR) seal other types of sheet metal joints, and A continuous, semi-flexible roof membrane, in various sealant applications. consisting of multiple plies of saturated felts, coated felts, fabrics, or mats assembled in Calender place with alternate layers of bitumen, and (1) To press between rollers or plates in surfaced with mineral aggregate, bituminous order to smooth and glaze, or to thin into materials, a liquid-applied coating or a sheets; (2) A machine for calendering.

A1-5 GLOSSARY APPENDIX 1

Camber Catalyst A slight convexity, arching, or curvature (as An ingredient that initiates a chemical of a rafter, joist, or substructure). reaction or increases the rate of a chemical reaction when combined with another Canopy chemical. Any overhanging or projecting roof structure, typically over entrances or doors. Cathodic A metal or material that readily attracts Cant electrons from an anodic material in the In SPF-based roofing, a beveling of foam at presence of an electrolyte. (See Galvanic horizontal/vertical joints to increase strength series.) and promote water runoff. Caulk Cant strip A composition of vehicle and pigment used A beveled strip used under flashings to at ambient temperatures for filling/sealing modify the angle at the point where the joints or junctures, that remains elastic for roofing or waterproofing membrane meets an extended period of time after application. any vertical element. Caulking Cap flashing (1) The physical process of sealing a joint (1) Usually composed of metal, used to or juncture; (2) Sealing and making cover or shield the upper edges of the weather-tight the joints, seams or voids membrane base flashing wall flashing; (2) A between adjacent surfaces by filling with a flashing used to cover the top of various sealant. buildings components, such as parapets or columns. (See Flashing and coping.) Cavitation The formation of a partial vacuum or cavity Cap sheet in a liquid. A sheet, often granule-surfaced, used as the top ply of some built-up or modified Cavity wall bitumen roof membranes and/or flashings. An exterior wall usually of masonry, consisting of an outer and inner withe Capacitance meter separated by a continuous air space, but A device used to locate moisture or wet connected together by wire or sheet-metal materials within a roof system by measuring tiles. the ratio of the change to the potential difference between two conducting CDX elements separated by a non-conductor. A grade of plywood in which the letter C specifies that one face of the plywood is a Capillary action veneer of grade C, which contains small (1) The action by which the surface of a knots and knotholes or splits that may have liquid, where it is in contact with a solid, is been plugged and sanded smooth. The elevated or depressed depending on the other face is a veneer of grade D, which relative attraction of the molecules of the can contain larger knots and may include liquid for each other and for those of the open splits and holes. The letter X signifies solid; (2) The siphoning of liquid into a joint that the adhesive used to make the or void between two adjacent surfaces. plywood is waterproof.

A1-6 GLOSSARY APPENDIX 1

Cee-channel Chemical resistance A structural framing member formed into The ability to withstand contact with the shape of the letter "c." specified chemicals without a significant change in properties. Cellular glass insulation A rigid closed-cell insulation board made Chimney from crushed glass and hydrogen sulfide Stone, masonry, prefabricated metal or gas. woodframed structure, containing one or more flues, projecting through and above Cementitious waterproofing the roof. Heavy cement-based compounds and various additives that are mixed and Chlorinated polyethylene (CPE) packaged for use in a dry form; the A thermoplastic material, used for single-ply packaged mixture is then mixed with water roof membranes, composed of high and liquid bonding agents to a workable molecular weight polyethylene that has concrete-like consistency. been chlorinated with a process that yields a flexible rubber-like material. Centipoise A unit of measure of absolute viscosity. (The Chlorosulfonated polyethylene (CSPE or viscosity of water is one centipoise. The CSM) lower the number, the less viscous the Probably best known by the DuPont trade material.) name Hypalon'", a synthetic, rubber-like thermoset material, based on high Centistoke molecular weight polyethylene with A unit of viscosity; the ratio of a liquid's sulphonyl chloride, usually formulated to absolute viscosity to the density of that liquid. produce a self-vulcanizing membrane. Classified by ASTM Standard D5019. Chalk A powdery residue on the surface of a Cladding material. A material used as the roof or exterior wall enclosure of a building. Chalk line A line made on the roof or other flat surface Cleat by snapping a taut string or cord dusted A continuous strip, or angled piece, used to with colored chalk. secure metal components. (See Clip.)

Chalking Clerestory The formation of a powdery surface An upward extension of enclosed space condition from the disintegration of a binder created by carrying a setback vertical wall or elastomer. (typically glazed) up and through the roof slope. Two intersecting shed roofs on Channel flashing different planes. In steep-slope roof construction, a type of flashing used at roof-to-wall junctures and Clip other roof-to-vertical plane intersections A component or angle piece used to secure where an internal gutter is needed to handle two or more metal components together. runoff. Commonly used with profile tile. (See Cleat.)

A1-7 GLOSSARY APPENDIX 1

Clipped gable Coal tar roof cement A gable cutback near the peak in a hiproof A trowel able mixture of processed coal tar form. base, solvents, mineral fillers and/or fibers. Classified by ASTM Standard D 4022, "Coal CIosed-cut valley Tar Roof Cement, Asbestos Container." A method of valley application in which shingles from one side of the valley extend Coarse orange peel surface texture across the valley, while shingles from the A surface showing a texture where nodules other side are trimmed back approximately and valleys are approximately the same size two inches (51 mm) from the valley and shape. This surface is acceptable for centerline. receiving a protective coating because of the roundness of the nodules and valleys. Closure strip A metal or resilient strip, such as neoprene Coated base sheet foam, used to close openings created by A coated felt intended to be used as a base joining metal panels or sheets and flashings. ply in a built-up or modified bitumen roof membrane. Coal tar A dark brown to black colored, semi-solid Coated fabric hydrocarbon produced by the distillation of Fabrics that have been impregnated and/or coal. Coal tar pitch is further refined to coated with a plastic-like material in the form conform to the following roofing grade of a solution, dispersion hot-melt, or powder. specifications: The term also applies to materials resulting from the application of a pre-formed film to a Coal tar pitch fabric by means of calendaring. A coal tar used as the waterproofing agent In dead-level or low-slope built-up Coated felt (Sheet) roof membranes and membrane (1) An asphalt felt that has been coated on waterproofing systems, conforming to both sides with harder, more viscous ASTM Specification D450, Type I. asphalt; (2) A glass fiber felt that has been simultaneously impregnated and coated Coal tar waterproofing pitch with asphalt on both sides. A coal tar used as the dampproofing or waterproofing agent in below-grade Coating structures, conforming to ASTM A layer of liquid or solid material applied to Specification D450, Type II. a surface for protection or appearance.

Coal tar bitumen Cobwebbing A proprietary trade name for Type III A phenomenon observed during spray coal tar used as the dampproofing or application characterized by the formation waterproofing agent In dead-level or of web-like threads along with the usual low-slope built-up roof membranes and droplets leaving the spray gun nozzle. membrane waterproofing systems, conforming to ASTM D450, Type III. Code Coal tar felt A collection of laws (regulations, ordinances A felt that has been saturated or or statutory requirements) adopted by impregnated with refined coal tar. governmental authority. (See Building code

A1-8 GLOSSARY APPENDIX 1 and Model code.) beyond to the apex of the ridge.

Coefficient of thermal expansion Combustible The coefficient of change in dimension of a Capable of burning. material per unit of dimension per degree change in temperature. Combustion A chemical process of oxidation that occurs Cohesion at a rate fast enough to produce heat and The molecular forces of attraction by which usually light, either as glow or flames; the the body of a material is held together. process of burning.

Coil coating Compatible materials The application of a finish to a coil of metal Two or more substances that can be mixed, using a continuous mechanical coating blended, or attached without separating, process. reacting, or affecting the materials adversely.

Cold forming Composite board roof insulation The process of shaping metal into desired Rigid board insulation generally comprised profiles without the application of heat. of perlite or wood fiberboard factory bonded to polyisocyanurate or polystyrene. Cold rolled The process of forming steel into sheets, Compounded thermoplastics panels, or shapes on a series of rollers at A category of roofing membranes made by room temperature. blending thermoplastic resins with plasticizers, various modifiers, stabilizers, Cold roof assembly flame retardants, UV absorbers, fungicides A roof assembly configured with the and other proprietary substances alloyed insulation below the deck, not typically in with proprietary organic polymers. contact with the deck, allowing for a ventilation space. The temperature of the Compressive strength roof assembly remains close to the outside The property of a material that relates to its air temperature. ability to resist compression loads.

Color stability Concealed-nail method The ability of a material to retain its original A method roofing application in which all color after exposure to weather. nails are driven into the underlying course of roofing and covered by a subsequent, Column overlapping course. In structures, a relatively long, slender structural compression member such as a Concealed plate post, pillar, or strut; usually vertical which acts (See Cover plate.) in (or near) the direction of its longitudinal axis. Condense To make denser or more compact, as when Combing ridge a material (e.g., water vapor) changes from A term used to describe an installation of its gas phase to its liquid phase. finishing slate or wood at the ridge of a roof whereby the slates on one side project

A1-9 GLOSSARY APPENDIX 1

Condensate in a concrete or masonry structure to The liquid resulting from the condensation regulate the location and amount of cracking of a gas. and separation resulting from the dimensional change of different parts of the Condensation structure, thereby avoiding the development The conversion of water vapor or other gas of high stresses. to liquid phase as the temperature drops; the act or process of condensing. Coping The covering piece on top of a wall Conditioning exposed to the weather, usually made of The storage of a material specimen under metal, masonry, or stone and sloped to specified temperature, humidity, etc. for a carry off water. specified time prior to testing. Copolymer Conductance, Thermal The product of polymerization of two or The thermal transmission in unit time more substances (as two different isomers) through unit area of a particular body or together. assembly having defined surfaces, when unit average temperature difference is Copolymerization established between the surfaces. C = Btu / A chemical reaction that results in the h • ft2 • °F (C = W / m2 • °K). bonding of two or more dissimilar monomers to produce large, long-chain molecules that Conductor head are copolymers. An enlargement or catch basin at the top of a downspout or leader to receive rainwater Copper from a gutter or scupper. A naturally weathering metal used in metal roofing or flashing; typically used in Construction joint 16 ounce per square foot (0.56 mm) and (1) A joint where two successive placements 20 ounce per square foot (0.69 mm) of concrete meet; (2) A separation provided thicknesses. in a building which allows its component parts to move with respect to each other. Core cut or core sample (1) A sample from a low-slope roof system Contact cements taken for the purpose of obtaining primarily Adhesives used to adhere or bond various qualitative information about its construction. roofing components. These adhesives Typically, core cut analysis can verify or adhere mated components immediately on reveal the type of membrane surfacing; the contact of surfaces to which the adhesive type of membrane, the approximate number has been applied. of plies; the type, thickness and condition of the insulation (if any): and the type of deck Contamination used as a substrate for the roof system. (2) The process of making a material or surface For SPF-based roof systems, core cuts are unclean or unsuited for its intended purpose, used to obtain both quantitative and usually by the addition or attachment of qualitative information, such as the thickness undesirable foreign substances. of the foam, the thickness and adhesion of the coating, thickness of individual passes Control joint and adhesion between passes and the A groove which is formed, sawed, or tooled adhesion of the foam to its substrate.

A1-10 GLOSSARY APPENDIX 1

Cornice Crack The decorative horizontal molding or A nonlinear separation or fracture occurring projected roof overhang. in a material.

Counter batten Cream time Vertical wood strips installed on sloped roofs Time in seconds (at a given temperature) over which horizontal battens are secured. when the A and B components of The primary roof covering is attached or polyurethane foam will begin to expand secured to these horizontal battens. after being mixed. Recognizable as a change in color of the materials. Counterflashing Formed metal or elastomeric sheeting Cricket secured on or into a wall, curb, pipe, rooftop A relatively small area of a roof constructed unit or other surface, to cover and protect to divert water from a horizontal intersection the upper edge of a base flashing and its of the roof with a chimney, wall, expansion associated fasteners. joint or other projection. (See Saddle.)

Course Cross-linking (1) The term used for a row of roofing The formation of chemical bonds between material that forms the roofing, waterproofing polymeric chains. Cross-linking of rubber is or flashing system; (2) one layer of a series of referred to as vulcanization or "curing." materials applied to a surface (e.g., a five- course wall flashing is composed of three Crystalline waterproofing applications of roof cement with one ply of felt A compound of cement quartz or silica or fabric sandwiched between two layers of sand, and other active chemicals that are roof cement). mixed and packaged for use in a dry powder form; the packaged mixture is then Cover board mixed with water and applied to a concrete An insulation board used over closed cell surface where it penetrates into the pores plastic foam insulation (e.g., polyiso- of concrete. cyanurate) to prevent blistering when used in conjunction with hot bituminous membranes. Cupola Suitable cover board insulation are A relatively small roofed structure, generally glassfaced siliconized gypsum board, glass- set on the edge or peak of a main roof area fiber board, perlite board, wood-fiber board or for ventilation or aesthetic purposes. mineral-fiber board. Cover boards are also recommended between polyisocyanurate Curb Insulation and Single ply membranes to (1) A raised member used to support roof protect the polyisocyanurate. penetrations, such as skylights, mechanical equipment, hatches, etc. above the level of Cover plate the roof surface; (2) A raised roof perimeter A metal strip sometimes installed over or relatively low in height. under the joint between formed metal pieces. Cure Coverage A process whereby a material is caused to The surface area uniformly covered by a form permanent molecular linkages by specific quantity of a particular material at a exposure to chemicals eat, pressure and/or specific thickness. weathering.

A1-11 GLOSSARY APPENDIX 1

Cure time Dead-level asphalt The time required for a material to reach its (See Asphalt.) desirable long-term physical characteristics. Dead loads Cured concrete The weight of a structure itself, including Concrete that has attained its intended the weight of fixtures or equipment design performance properties. permanently attached to it.

Curing agent Deck An additive in a coating or adhesive that A structural component of the roof of a results in increased chemical activity building. The deck must be capable of safely between the components with an increase supporting the design dead and live loads, or decrease in rate of cure. including the weight of the roof system's additional live loads required by the Curing compound governing building codes, and provide the A liquid that is sprayed or otherwise applied substrate to which the roofing or to newly placed concrete which retards the waterproofing system is applied the structural loss of water during curing. surface of a building to which a roof assembly is installed. Decks are either non-combustible Curved roof (e.g., corrugated metal, or concrete) or A roof whose panels are mounted on a combustible (e.g., wood plank or plywood). barrel or dome support. Deflection (bowing, sagging) Cutback (1) The deformation of a structural member Solvent-thinned bitumen used in cold- as a result of loads acting on it: (2) Any process roofing adhesives, roof cements and displacement in a body from its static roof coatings. position, or from an established direction or plane, as a result of forces acting on the Cutoff bod. A permanent detail designed to prevent lateral water movement in an insulation Degradation system and used to isolate sections of a A harmful change in the chemical structure, roofing system. (Note: A cutoff is different physical properties or appearance of a from a tie-in, which may be a temporary or material from natural or artificial exposure permanent seal.) (See Tie-In.) (e.g., exposure to radiation moisture, heat, freezing, wind, ozone, oxygen, etc.). Cutout The open portions of a strip shingle between Degree days the tabs. Sometimes referred to as a keyway. A unit used in estimating the fuel consumption for a building; equal to the Dampproofing number of degrees that the mean Treatment of a surface or structure to resist temperature, for a 24-hour day, is below the the passage of water in the absence of "base temperature"; the base temperature hydrostatic pressure. is taken as 65° F (18.3° C) in the U.S.A.

Dead level Delamination Absolutely horizontal or zero slope. (See Separation of the laminated layers of a Slope.) component or system.

A1-12 GLOSSARY APPENDIX 1

Design loads least 2 inches (50 mm) wider than the The total load on a structural system for the exposed portion, resulting in two layers of most severe combination of loads and roofing material over the deck. forces which it is designed to sustain. Double lock standing seam Dew-point temperature In a metal roof panel or metal cap, a The temperature at which air becomes standing seam that uses a double saturated with water vapor. The temperature overlapping interlock between two metal at which air has a relative humidity of 100%. panels. (See Standing seam.)

Diaphragm Double pour A floor slab, metal wall panel, roof panel, or To apply two layers or flood coats of the like having a sufficiently large in-plane bitumen and aggregate to a built-up roof. shear stiffness and sufficient strength to transmit horizontal forces to resisting Downspout systems. A vertical pipe or conduit used to carry runoff water from a scupper, conductor Diffusion head, or gutter of a building to a lower roof The movement of water vapor from regions level or to the ground or storm water runoff of high concentration (high water vapor system. pressure) toward regions of lower concentration. Drag load The external force (e.g., from the weight of Dimensional shingle ice and snow) applied to a steep-slope roof A shingle that is textured, overlayed, or system component forcing the component laminated and designed to produce a three downslope. dimensional effect. (also see Laminated shingle and Architectural shingle.) Drain An outlet or other device used to collect and Dimensional stability direct the flow of runoff water from a roof The degree to which a material maintains area. its original dimensions when subjected to changes in temperature and humidity. Drip edge A metal flashing or other overhanging Diverter component with an outward projecting An upslope barrier to water often installed lower edge, intended to control the direction in close proximity to chimneys, curbs, or of dripping water and help protect other roof obstructions, in order to direct underlying building components. drainage. Dry Dormer (1) Free or relatively free from a liquid, A structure projecting from a sloping roof especially water; (2) To remove water or usually housing a window or ventilating moisture. louver. Dry bulb temperature Double coverage The temperature of air as measured by an Application of asphalt, slate, or wood ordinary thermometer. rooting such that the lapped portion is at

A1-13 GLOSSARY APPENDIX 1

Dry film thickness Efflorescence The thickness, expressed in mils, of an An encrustation of soluble salts, commonly applied and cured coating or mastic. For white, deposited on the surface of stone, comparison, see Wet film thickness. brick, plaster, or mortar; usually caused by free alkalies leached from mortar or Drying time adjacent concrete as moisture moves The time required for the loss of volatile through it. components so that the material will no longer be adversely affected by weather Elasticity conditions such as dew, rain, or freezing. The property of a body that causes it to tend to return to its original shape after Dual level drain deformation (as stretching, compression, or In waterproofing, an outlet or other device torsion). with provisions for drainage at both the wearing surface and waterproofing Elastomer membrane levels used to collect and direct A macromolecular material that returns the flow of runoff water from a horizontal slab. rapidly to its approximate initial dimensions and shape after substantial deformation by Dynamic load a weak stress and subsequent release of Any load which is nonstatic, such as a wind that stress. load or moving live load. Elastomeric coating Eave A coating that is capable of being stretched The lower edge of a sloping roof that part of at least twice its original length (100 percent a roof which projects beyond the wall. elongation) and. recovering to its original dimensions. Eave height The vertical dimension from finished grade Elongation to the eave. The ratio of the extension of a material to the length of the material prior to stretching. Eave-trough See Gutter. Embedment (1) The process of pressing/positioning a Edge stripping felt, aggregate, fabric, mat, or panel into hot Membrane flashing strips cut to specific bitumen or adhesive to ensure intimate widths used to seal/flash perimeter edge contact at all paints; (2) The process of metal and the roof membrane application of pressing/positioning granules into coating in felt strips cut to narrower widths than the the manufacture of factory-prepared normal felt-roll width to cover a joint roofing, such as shingles. between metal perimeter flashing and built- up roofing. Embossed To raise a design, or pattern, on (a blank) Edge venting with dies of similar pattern, one the The practice of providing regularly spaced negative of the other. or continuously protected (e.g., louvered) openings along a roof edge or perimeter. Embrittlement used as part of a ventilation system to The loss of flexibility or elasticity of a dissipate heat and moisture vapor. material.

A1-14 GLOSSARY APPENDIX 1

Emulsion Ethylene propylene diene terpolymer A mixture of bitumen and water, with (EPDM) uniform dispersion of the bitumen or water, Designated nomenclature of ASTM for a globules, usually stabilized by an terpolymer of ethylene, propylene and emulsifying agent or system. diene. EPDM material is a thermosetting synthetic elastomer. End lap The distance of overlap where one ply, Exhaust ventilation pane, or piece extends beyond the end of Air that is vented or exhausted from the roof the immediately adjacent underlying ply, cavity, typically through vents installed on panel, or piece. the up slope portion of the roof. For example, with most steepslope roof Energy star assemblies, exhaust vents are typically A joint program of the U.S. Environmental located at or near the ridge. Protection Agency and the U.S. Department of Energy helping us save money and Exotherm protect the environment through energy Heat generated by a chemical reaction. efficient products and practices. Expansion cleat Envelope (Bitumen-stop) A cleat designed to accommodate thermal A continuous membrane edge seal formed movement of metal roof panels. at the perimeter and at penetrations by folding the base sheet or ply over the plies Expansion joint above and securing it to the top of the A structural separation between two membrane. The envelope prevents bitumen building elements that allows free seepage from the edge of the membrane. movement between the elements without damage to the roofing or waterproofing EPDM system. Ethylene propylene diene monomer. (See also Ethylene propylene diene terpolymer.) Exposed-nail method A method of asphalt roll roofing application Epichlorohydrin (ECH) in which all nails are driven into the A synthetic rubber including two adhered, overlapping course of roofing. epichlorohydrin based elastomers. It is Nails are exposed to the weather. similar to and compatible with EPDM. Exposure Epoxy (1) The traverse dimension of a roofing A class of synthetic, thermosetting resins element or component not overlapped by that produce tough, hard, chemical- an adjacent element or component in a roof resistant coatings and adhesives. covering. For example, the exposure of any ply in a built-up roof membrane may be Equilibrium moisture content (EMC) computed by dividing the felt width, minus The moisture content of a material 2 inches (51 mm), by the number of stabilized at a given temperature and shingled plies; thus, the exposure of 36 inch relative humidity, expressed as percent (914 mm) wide felt in a shingled, four-ply moisture by weight. membrane should be approximately 8 inches (216 mm); (2) The dimension of sidewall or roofing covering that is not covered or

A1-15 GLOSSARY APPENDIX 1 overlapped by the up-slope course of avoid injuries and death due to falling from component. The typical exposure for a a roof or other elevation. standard-sized three-tab shingle is 5 inches (127 mm), depending on manufacturer Fallback specifications. A reduction in bitumen softening point, sometimes caused by refluxing or Extrusion overheating in a relatively closed container. A process in which heated or unheated (See Softening point drift.) material is forced through a shaping orifice (a die) in one continuously formed shape, Fascia as in film, sheet, rod, or tubing. (1) In steep-slope roofing, a board that is nailed to the ends of a roof rafter; Eyebrow sometimes supports a gutter; (2) In low- A dormer, usually of small size, whose roof slope roofing, the vertical or steeply sloped line over the upright face is typically an roof or trim located at the perimeter of a arched curve, turning into a reverse curve building. Typically, it is a border for the low- to meet the horizontal at either end. Also, a slope roof system. small shed roof projecting from the gable end of the larger, main roof area. Fastener Any of a wide variety of mechanical Fabric securement devices and assemblies, A woven cloth or material of organic or including nails, staples, screws, cleats, clips inorganic filaments, threads, or yarns used and bolts, which may be used to secure for reinforcement in certain membranes and various components of a roof assembly. flashings. Feathering strips Factory Mutual Research Corporation Tapered wood filler strips placed along the (FMRC) butt ends of old wood shingles to create a Factory Mutual Research Corporation is an relatively smooth surface when reroofing organization devoted in general to property over existing wood shingle roofs. Referred conservation. Its activities include writing to in some regions of the country as "horse internal standards; participating in the writing feathers," or leveling strips. of consensus standards; third-party testing and approval of products; and certification of Felt electrical apparatus for shock and fire safety. A flexible sheet manufactured by the Their concern includes fire-safety, electrical, interlocking of fibers with a binder, or and construction-related issues. through a combination of mechanical work, moisture, and heat. Felts are manufactured Factory seam principally from wood pulp and vegetable A splice/seam made by the manufacturer fibers (organic felts), asbestos fibers during the assembly of sections of materials (asbestos felts), glass fibers (glass fiber into larger sheets/panels. felts or ply Sheets), or polyester fibers.

Fading Felt machine (Felt Layer) Any lightening of initial color. A mechanical device used for applying bitumen and roofing felt or ply sheet Fall protection simultaneously. Critical safety equipment used in order to

A1-16 GLOSSARY APPENDIX 1

Ferrule to prevent sticking. A metal sleeve placed inside a gutter at the top. A spike or screw is nailed/screwed Fire barrier through the gutter face and ferrule into the An assembly component which is rated or fascia board to hold the gutter in place. The classified and used to provide fire ferrule acts as a spacer in the gutter to resistance. Common examples are maintain its original shape. fiberglass underlayment and gypsumboard.

Field seam Fire resistance A splice or seam made in the field (not The property of a material or assembly to factory) where overlapping sheets are withstand fire or give protection from it. joined together using an adhesive, splicing tape, or heat- or solvent-welding. Fire retardant treated (FRT) plywood Plywood which has been impregnated, under Filler pressure, with mineral salts; in the event of A relatively inert ingredient added to modify fire, the burning wood and salts emit physical characteristics. noncombustible gases and water vapor instead of the usual flammable vapors. Fillet A heavy bead of waterproofing compound Fishmouth or sealant material generally installed at the (Also referred to as an edge wrinkle) (1) A point where vertical and horizontal surfaces half-cylindrical or half-conical shaped opening meet; to reduce the desired effect to take or void in a lapped edge or seam, usually out the 90° angle at the base of a vertical caused by wrinkling or shifting of ply sheets flashing. during installation; (2) In metal panels or shingles, a half-conical opening formed at a Film cut edge. Fishmouths in an installation may Sheeting having a nominal thickness not be an aesthetic or a performance issue. greater than 10 mils (0.25 mm). Flaking Film thickness In protective coatings, the detachment of The thickness of a membrane or coating. Wet small pieces of the coating film. film thickness is the thickness of a coating as applied; dry film thickness is the thickness Flammable after curing. Film thickness is usually Subject to easy ignition and rapid flaming expressed in mils (thousandths of an inch). combustion.

Fin Flame retardant A term used to describe a deck surface A chemical used to impart flame resistance. condition. A sharp raised edge (generally in concrete) capable of damaging a roof Flame spread membrane or vapor retarder. The propagation of a flame away from its source of ignition. Fine mineral-surfacing Water-insoluble, inorganic material, more Flammability than 50 percent of which passes through a Those characteristics of a material that No. 35 sieve. Used on the surface of pertain to its relative ease of ignition and various roofing materials and membranes ability to sustain combustion.

A1-17 GLOSSARY APPENDIX 1

Flange Flood (pour) coat The projecting edge of a rigid or semi-rigid The surfacing layer of bitumen into which component, such as a metal edge flashing surfacing aggregate is embedded on an flange. aggregate surfaced built-up roof.

Flash point Flood test The lowest temperature at which vapors The procedure in which a controlled amount above a volatile combustible substance of water is temporarily retained over a ignite in air when exposed to a flame. horizontal surface to determine the effectiveness of the waterproofing system. Flashing Components used to weatherproof or seal Fluid-applied elastomer roof system edges at perimeters, A liquid elastomeric material that cures after penetrations, walls, expansion Joints, application to form a continuous valley, drains and other places where the waterproofing membrane. roof covering is interrupted or terminated. For example, membrane base flashing Fly-in covers the edge of the field membrane, and Method of application for roll materials by cap flashings or counterflashings shield the which the dry sheet is set into the bitumen upper edges of the base flashing. or adhesive applied to the roof surface.

Flashing cement FM, FMR, or FMRC A trowelable mixture of solvent-based See Factory Mutual Research Corporation bitumen and mineral stabilizers that may (FMRC). include asbestos or other inorganic or organic fibers. Generally, flashing cement is Foam stop characterized as vertical-grade, which The roof edge treatment upon which SPF is indicates It is Intended for use on vertical terminated. surfaces. (See Asphalt roof cement and plastic cement.) Force A strength or energy exerted or brought to Flashing collar bear because of motion or change. (Sometimes referred to as a roof jack or flashing boot) an accessory flashing used to Froth pack cover and/or seal soil pipe vents and other A term used to describe small, disposable penetrations through the roof. aerosol cans that contain SPF components. Two component froth packs are available to Flat lock do small repairs for sprayed polyurethane A method of interlocking metal panels in foam-based roofs. which one panel edge is folded back on top of itself and the other panel is folded under, G90 after which the two panels are hooked A designation for galvanized metal sheet, together. indicating 0.90 ounces (26 grams) of zinc per square foot, measured on both sides Fleece per ASTM A653. Mats or felts composed of fibers, sometimes used as a membrane backer. Gable The vertical triangular portion of the end of

A1-18 GLOSSARY APPENDIX 1 a building having a double-sloping roof, from Girt the level of the eaves to the ridge of the roof. A horizontal beam that supports wall cladding between columns. Gable roof A single-ridge roof that terminates at gable Glass fiber insulation end(s). Blanket or rigid board insulation, composed of glass fibers bound together with a binder, Galvalume faced or unfaced, used to insulate roofs and Trade name for a coated steel sheet walls. product whose coating is a metal alloy composed of aluminum, zinc, and silicone. Glass felt Glass fibers bonded into a sheet with resin Galvanic action and suitable for impregnation with asphalt An electrochemical action that generates in the manufacture of bituminous water- electrical current between two metals of proofing, roofing membranes and shingles. dissimilar, electrode potential. Glass mat Galvanic series A thin mat of glass fibers with or without a A list of metals and alloys arranged according binder. to their relative electrolytic potentials in a given environment. Glaze coat (1) The top layer of asphalt on a smooth- Galvanize surfaced built-up roof membrane; (2) A thin To coat steel or iron with zinc. protective coating of bitumen applied to the lower plies or top ply of a builtup roof Galvanized steel membrane when application of additional Steel coated with zinc for corrosion felts or the flood coat and aggregate resistance. surfacing are delayed. (See Flood coat.)

Gambrel Gloss A roof that has two pitches on each side, The shine, sheen or luster of a dried film. where the upper roof area has less slope than the lower roof areas. Goof screw A large diameter fastener used to replace a Gauge stripped out fastener in sheet metal roof or A metal thickness measurement. siding panels.

Geocomposite Grain A prefabricated water drainage material A unit of measure in the English System of used to reheve hydrostatic pressure against units; 7,000 grains equals 1 lb.; used as a waterproofing and promote drainage. measure of the weight of moisture in air.

Geotextile Granule A tightly woven fabric used to restrict the (Also referred to as mineral or ceramic flow of fine soil particles and other granule) opaque, natural or synthetically contaminants while allowing water to pass colored aggregate commonly used to freely through; used to protect drainage surface cap sheets, shingles, and other systems from clogging. granule-surfaced roof coverings.

A1-19 GLOSSARY APPENDIX 1

Gravel Heat flow Coarse granular aggregate resulting from The quantity of heat transferred to or from a the natural erosion of rock. system in a unit of time.

Gravel stop Heat seaming A flanged device, frequently metallic, The process of joining thermoplastic films, designed to prevent loose aggregate from membranes, or sheets by heating and then washing off the roof and to provide a applying pressure to bring both materials in continuous finished edge for the roofing. contact with each other. (See Heat welding.)

Groundwater level Heat transfer At a particular site, the level, below which The transmission of thermal energy from a the subsoil and rock masses of the earth location of higher temperature to a location are fully saturated with water. of lower temperature. This can occur by conduction, convection or radiation. Grout A mixture of cement, sand, and water used Heat welding to fill cracks and cavities in masonry. Method of melting and fusing together the overlapping edges of separate sheets or Gusset sections of polymer modified bitumen, Used at the bottom of a steep-slope roof thermoplastics or some uncured thermoset system valley, a large flat metal piece(s) roofing membranes by the application of wider than the valley to help prevent build- heat (in the form of hot air or open flame) up at the base of the valley, either from and pressure. (See Heat seaming.) debris or ice dam formations. Hem Gutter The edge created by folding metal back on A channeled component installed along the itself. downslope perimeter of a roof to convey runoff water from the roof to the drain Hip leaders or downspouts. The inclined external angle formed by the intersection of two sloping roof planes. Gypsum board panels Cementitious board stock with non- Hip roof combustible core primarily comprised of A roof that rises by inclined planes to form gypsum that is commonly used as a barrier one or more hips. board thermal barrier or cover board in a roof assembly. Hoist A mechanical lifting device. Hand-tabbing Method of spot applying asphalt-based Holiday adhesive to shingles for securement and An area where a liquid-applied material is wind resistance. missing or absent.

Headlap Honeycomb The distance of overlap measured from the Voids left in concrete resulting from failure uppermost ply or course to the point where of the mortar to effectively fill the spaces it laps over the undermost ply or course. among coarse aggregate particles.

A1-20 GLOSSARY APPENDIX 1

Hot or Hot stuff polyethylene" (CSPE). (see Chlorosulfonated A roofing worker's term for hot bitumen. polyethylene.)

Hue Ice dam The subjective perception of color such as A mass of ice formed at the transition from red, yellow, green, blue, purple or some a warm to a cold roof surface. Frequently combination; white, black or gray possess formed by the refreezing of meltwater at the no hue. overhang of a steep roof, causing ice and water to back up under roofing materials. Humidity Usually resolved by correcting insulation The condition of the atmosphere with respect gaps. to water vapor. See relative humidity. Ice dam protection membrane Hybrid roof covering A membrane installed under steep slope Combination of two or more separate and roofing materials in areas subject to ice distinct roof membranes; e.g., three ply damming that prohibits water which gets smooth BUR and a modified bitumen cap. through the roof covering from getting into the structure. Must also seal the fasteners Hydration that penetrate it. The chemical reaction by which a substance (such as Portland cement) Ignition temperature combines with water, giving off heat to form The lowest temperature at which a crystalline structure in its setting and combustion will occur spontaneously under hardening. specific conditions.

Hydrocarbon Impact resistance An organic chemical compound primarily Resistance to fracture under the sudden containing the elements carbon and application of an exerted force. hydrogen. Impregnate Hydrostatic pressure In roofing materials manufacture, to The pressure equivalent to that exerted on completely surround the fibers in a felt or a surface by a column of water of a given mat with bitumen with the spaces between height. the fibers partially or completely filled without a continuous coating of bitumen on Hydrostatic pressure relief system the surface. A system of perimeter and/or under slab drains used to regulate the hydrostatic Infrared thermography pressure in the earth surrounding a below The process of displaying variations of grade structure. apparent temperatures (variation of temperature or emissivity or both) over the Hygroscopic surface of an object by measuring Attracting, absorbing and retaining variations in infrared radiance. atmospheric moisture. Insulated Metal Panels Hypalon™ A homogeneous assembly of an exterior A registered trademark of E.I. Du Pont de and interior metal face chemically bonded Nemours & Co., for "chlorosulfonated to a foam core. The manufacturing process

A1-21 GLOSSARY APPENDIX 1 can use either foamed in place or laminated "protected membrane roof assembly" in methods to create the panel. The panels which Styrofoam® brand insulation and are produced with various profiles and ballast are placed over the roof membrane. joints. The panels are designed for function IRMATM and Styrofoam® are registered as a one piece water, vapor, and insulation trademarks of the Dow Chemical Company. barrier. Composite Insulated Panels can be used for roof, wall, soffit and partitions. Isocyanate A highly reactive organic chemical containing Inorganic one or more Isocyanate (-N=C=O) groups. A Being or composed of materials other than basic component in SPF based systems and hydrocarbons and their derivatives, or some polyurethane coating systems. matter that is not of plant or animal origin. Insect screen Isolation sheet Wire mesh used to prevent insects from Refer to slip sheet. entering the building through ventilators louvers or other openings. Joist Any of the small timbers, metal or wood In-service R-value beams arranged parallel to each other and Thermal resistance value established under spanning from wall to wall to support a installed conditions and measured over the floor, ceiling, or roof of a building. expected service life of the material. Joule Insulation A unit of energy or work; equals the work Any of a variety of materials designed to done by a force of 1 newton which acts over reduce the flow of heat, either from or into a a distance of 1 meter in the direction of the building. (See Thermal insulation.) force.

Intake ventilation k or k-Value The fresh air that is drawn into a passive Thermal conductivity; the time rate of heat ventilation system through vents typically flow through a unit area of a homogeneous installed in soffit or eave of a roof. material in a direction perpendicular to isothermal planes induced by a Unit Interlayment temperature gradient. In English (inch- A felt, metal, or membrane sheet material pound) units of measurement, it is the used between courses of steep-slope roofing number of BTUs that pass through a 1 Inch to improve weather- and water-shedding (25 mm) thickness of a 1 square foot (0.09 characteristics of the primary roof covering m2) sample of material in 1 hour with a during times of wind-driven precipitation. temperature difference between the two Typically used with wood shakes. surfaces of 1°F. It is expressed as Btu•inch / h•ft2 •F. Interlocking shingles Individual shingles that mechanically attach Kerf to each other to provide enhanced wind (1) A slit or notch made by a saw or cutting resistance without reliance on sealing strips. torch; (2) the width of cut made by a saw or cutting torch. Inverted roof membrane assembly (IRMA™) Kesternich test A patented, proprietary variation of the Simulates acid rain conditions by subjecting

A1-22 GLOSSARY APPENDIX 1 test specimens to a sulfur dioxide seamed, sealed or otherwise bonded. atmosphere as well as condensing moisture for the purpose of evaluating rust / corrosion Latex characteristics. A stable dispersion of polymeric substance in an essentially aqueous medium. Knee cap A metal cover trim that fits over a panel rib Lead after it has been cut and bent. A soft malleable, heavy metal; has low melting point and a high coefficient of Knee joints thermal expansion. (See Knuckle.) Leader head Knuckle (See Conductor head.) A metal closure, either shop-or pre- fabricated installed over the cut seam of a Lift continuous metal roof panel at the transition The sprayed polyurethane foam that results from a steep-slope roof to a vertical roof or from a pass. It usually is associated with a wall. certain pass thickness and has a bottom layer, center mass and top skin in its Laitance makeup. A weak layer of cement and aggregate lines on a concrete surface that is usually caused Liquid-applied by an overwet mixture, overworking the Application of bituminous cements, mixture, improper or excessive finishing or adhesives or coatings installed at ambient combination thereof. or slightly elevated temperatures.

Laminate Liquid-applied built-up roof To join layers of materials together using A continuous, semi-flexible roof membrane, fusion; the process of joining layers of consisting of multiple plies of felts, mats or materials together using adhesion. fabrics laminated together with alternate layers of roof cements and surfaced with a Laminated shingles liquid-applied coating with or without See Dimensional Shingles or Architectural aggregate surfacing. Shingles. Live loads Lap Temporary loads that the roof structure That part of a roofing, waterproofing, or must be designed to support, as required flashing component that overlaps or covers by governing building codes. Live loads are any portion of the same or another type of generally moving and/or dynamic or adjacent component. environmental, (e.g., people, installation equipment, snow, ice or rain, etc.). Lap cement An asphalt-based roof cement formulated to Loose-laid membrane adhere overlapping plies or asphalt roll A ballasted roofing membrane that is roofing. attached to the substrate only at the edges and penetrations through the roof. Lap seam Occurs where overlapping materials are

A1-23 GLOSSARY APPENDIX 1

Low-slope roofs product and other pertinent data, including A category of roofs that generally include such things as safe handling and weatherproof membrane types of roof emergency procedures. In accordance with systems installed on slopes 2 or 3 but less OSHA regulations, it is the manufacturer's than 3:12 (14 degrees) that require weather responsibility to produce an MSDS and the proof joinery. employers responsibility to communicate its contents to employees. Low temperature flexibility The ability of a membrane or other material Mechanical damage to resist cracking when flexed after it has Physical damage to a roof system not been cooled to a low temperature. caused by normal wear and tear.

Machine seam Mechanically fastened membranes See mechanical seam. Generally used to describe membranes that have been attached at defined intervals to Mansard the substrate. A decorative steep-sloped roof on the perimeter of a building. Mechanical seam Metal Roof system which requires that Mansard roof panels require to be engaged with a A steeper roof that terminates into a flat mechanical seaming tool. Also called roof at its high point. Machine seam.

Masonry Membrane Construction, usually set in mortar, of A flexible or semi-flexible roof covering or natural building stone or manufactured waterproofing whose primary function is to units, such as brick, concrete block, adobe, exclude water. glass block, tile, manufactured stone or gypsum block. Metal A solid material that is typically hard, shiny, Mastic malleable, fusible, and ductile, with good A thick adhesive material used as a electrical and thermal conductivity. cementing agent for holding waterproofing Metal rain collar membrane in place. (See Asphalt roof A metal counterflashing used to wrap a cement.) penetration and prevent water infiltration though the top of the penetration base Mat flashing. A thin layer of woven, non-woven, or knitted fiber that serves as reinforcement to a Meter material or membrane. Unit of length measurement in the metric system; 1 meter is equal to 39.37 inches. Mat slab A concrete slab designed with rein- Metal roof panel forcement to resist the uplift forces created An interlocking metal sheet creating a roof by hydrostatic pressure. cladding.

Material safety data sheets (MSDS) Metal roof shingle A written description of the chemicals in a An interlocking metal sheet or

A1-24 GLOSSARY APPENDIX 1 discontinuous sheet often simulating regulations pertaining to building traditional materials such as wood, asphalt, construction. or tile. Modified bitumen Mil (1) A bitumen modified by including one or A unit of measure, one mil is equal to 0.001 more polymers (e.g., atactic polypropylene, inches, or 25.4 micrometers (µm), often styrene butadiene styrene, etc.); (2) used to indicate the thickness of a roofing Composite sheets consisting of a polymer membrane. modified bitumen often reinforced with Mildew various types of mats or films and A superficial growth produced on organic sometimes surfaced with films, foils or matter or living plants by fungi. mineral granules. Millimeter Moisture contour map A unit of measure equal to one thousandth A map used to graphically define the (0.001) of a meter, or 0.03937 inches. location of moisture within a roof assembly after a moisture scan has been performed. Mineral fiber Insulation composed principally of fibers Moisture relief vent manufactured from rock, slag or glass, with A venting device installed through the or without binders. roofing membrane to relieve moisture vapor pressure from within the roofing system. Mineral granules (See Granules.) Moisture scan The use of a mechanical device Mineral stabilizer (capacitance, infrared, or nuclear) to detect A fine, water-insoluble inorganic material, the presence of moisture within a roof used in a mixture with solid or semi-solid assembly. (See Nondestructive testing.) bituminous materials. Mole run Mineral-surfaced roofing A meandering ridge in a roof membrane not Roofing materials whose surface or top associated with insulation or deck joints. layer consists of a granule surfacing. Monolithic Mineral-surfaced sheet Formed from or composed of a single A roofing sheet that is coated on one or material; seamless. both sides with asphalt and surfaced with mineral granules. Monomer A low-molecular-weight substance consisting Miter joint of molecules capable of reacting with like or A joint between two members at an angle to unlike molecules to form a polymer. each other; each member is cut at an angle equal to half the angle of the junction; Mop-and-flop usually the members are at right angles to An application procedure in which roofing each other. elements (insulation boards, felt plies, cap sheets, etc.) are initially placed upside Model (building) codes down adjacent to their ultimate locations; A compilation of standards or codes coated with adhesive or bitumen; and established to provide uniformity in turned over and adhered to the substrate.

A1-25 GLOSSARY APPENDIX 1

Mopping Neoprene The application of hot bitumen with a mop A synthetic rubber (polychloroprene) used or mechanical applicator to the substrate or in liquid and sheet-applied elastomeric roof plies of a bituminous membrane. There are membranes or flashings. four types of mopping. Nesting Solid mopping (1) The installation of new metal roof deck A continuous coating. directly on top of existing metal roof deck; (2) A method of reroofing with new asphalt Spot mopping shingles over existing shingles in which the Bitumen is applied roughly in circular top edge of the new shingle is butted areas, leaving a grid of un-mopped against the bottom edge of the existing perpendicular areas. shingle.

Sprinkle mopping Net free vent area Bitumen is shaken onto the substrate The area (measured in square inches) open from a broom or mop in a random to unrestricted air flow and commonly used pattern. as a yardstick to measure relative vent performance; the area of the opening of a Strip mopping vent minus the area displaced by the Bitumen is applied in parallel bands. screening material.

Mud cracking Newton (N) Surface cracking resembling a dried mud flat. SI unit of measure for force.

Mud slab Night seal (or night tie-in) A layer of concrete, typically 2 inches A material and/or method used to (50 mm) to 6 inches (150 mm) thick, used temporarily seal a membrane edge during as the substrate for membrane waterproofing. construction to protect the roofing assembly in place from water penetration. Usually Nailer removed when roofing application is (Sometimes referred to as blocking) a piece resumed. or pieces of dimensional lumber and/or plywood secured to the structural deck or Nitrile rubber walls, which provide a receiving medium for A membrane whose predominant resinous the fasteners used to attach membrane or ingredient is a synthetic rubber made by the flashing. polymerization of acrylonitrile with butadiene. Nail Flange Panel A concealed fastener roof panel typically Noble metal using screw fasteners through a flange to A metal that readily receives electrons from secure the panel to the structure. an anodic metal (See Galvanic series).

Negative side waterproofing Nondestructive testing (NDT) An application wherein the waterproofing A method to evaluate the disposition, system and source of hydrostatic pressure strength or composition of materials or are on opposite sides of the structural systems without damaging the object under element. test. Typically used to evaluate moisture

A1-26 GLOSSARY APPENDIX 1 content in roofing assemblies, the three by a gauge that is used to detect hydrogen; common test methods are electrical the quantity of hydrogen detected may be capacitance, infrared thermography and linked to the pressure of water. nuclear back-scatter. Nylon Nonflammable Generic name for a family of polyamide Not easily ignited and not burning rapidly if polymers, used as a scrim in some fabric- ignited. reinforced sheeting.

Nonfriable Off-ratio foam A material that, when dry, cannot be SPF that has excess isocyanate or resin. crumbled, pulverized or reduced to powder Off-ratio will not exhibit the full physical by hand pressure. properties of normal SPF.

Nonoxidizing Oil canning A material which resists oxidation in exterior The perceived waviness in the flat areas of exposures or accelerated weathering. roofing and siding panels.

Non-structural panel Open time A metal roof panel, typically a double The period of time after an adhesive has standing seam or batten seam; generally been applied and allowed to dry, during requires solid decking underneath and which an effective bond can be achieved by relies on slope to shed water. Also see joining the two surfaces. Architectural panel. Open valley Non-traffic bearing A method of valley construction in which the For waterproofing purposes, a membrane steep-slope roofing on both sides are system requiring some form of protection trimmed along each side of the valley, barrier and wearing surface. exposing the metal valley flashing.

Nonvolatile content Orange peel surface texture The portion of a coating that does not In SPF roofing, a condition of the foam in evaporate during drying or curing under which the surface shows a fine texture and specified conditions, comprising the binder is compared to the exterior skin of an and, if present, the pigment. (The percent orange. This surface is considered volatile content is obtained by subtracting acceptable for receiving a protective coating. the nonvolatile content from 100.). Organic Nonwoven fabric Being or composed of hydrocarbons or their A textile structure produced by bonding or derivatives, or matter of plant or animal interlocking of fibers, or both, accomplished origin. by mechanical, chemical, thermal, or solvent means and combinations thereof. Organic felt An asphalt roofing base material Nuclear hydrogen detection (NHO) meter manufactured from cellulose fibers. A device that contains a radioactive source to emit high velocity neutrons into a roof Organic shingle system. Reflecting neutrons are measured An asphalt shingle reinforced with material

A1-27 GLOSSARY APPENDIX 1 manufactured from cellulose fibers. deteriorating effects of ozone exposure.

OSB Pallet Oriented Strand Board. An engineered wood- A platform (typically wooden) used for based panel consisting of strands of wood storing and shipping materials. which are bonded together with a synthetic resin; the strands are pressed together in Pan layers. In the outer layers strands are The bottom flat part of a roofing panel that generally oriented longitudinally in line with is between the ribs of the panel. the panel length, whereas in the middle Pan former layers strands generally lie in a cross wise Power roll-forming equipment that produces direction. OSB is readily identified by its a metal roofing panel from a flat sheet. Also relatively large and long wood strands. known as a roll former or panel former.

Osmosis Parapet wall Movement of a solvent through a The part of a perimeter wall that extends semipermeable membrane into a solution of above the roof. higher solute concentration that tends to equalize the concentration of solute on the Parge two sides of the membranes. In masonry construction, a coat of cement mortar on the face of rough masonry, the Overflow drainage earth side of foundation and basement Component in a roof drainage system used walls, or the like. to protect the roof against damage from a water load imposed by blocked or partially Partially attached blocked primary drainage system; e.g., A roofing assembly in which the membrane overflow scupper, overflow interior drain. has been "spot affixed" to a substrate, usually with an adhesive or a mechanical device. Overspray Undesirable depositions of airborne spray. Parting agent A material applied to one or both surfaces Overspray surface texture of a sheet to prevent blocking. In SPF roofing, a condition of the foam in which the surface shows a linear coarse Pascal textured pattern and/or a pebbled surface. SI unit of measure for force per unit area; This surface is generally downwind of the 1 Pa = 1 N / m2. sprayed polyurethane path and, if severe, unacceptable for proper coating coverage Pass and protection. (1) A layer of material, usually applied by the spray method, that is allowed to reach Ozone cure before another layer ("pass") is A triatomic form of oxygen that is a bluish applied; (2) A term used to explain a spray gas of pungent odor; is formed naturally in motion of the foam gun in the application of the upper atmosphere by a photochemical the spray polyurethane foam (SPF) reaction with solar ultraviolet radiation. material. The speed of the pass controls the thickness of the SPF. Ozone resistance The ability of a material to resist the

A1-28 GLOSSARY APPENDIX 1

Pass line Permeance The junction of two passes of SPF. A (1) The rate of water vapor transmission per distinct line is formed by the top skin of the unit area at a steady state through a bottom pass and the next pass adhering to material, membrane, or assembly; (2) The this skin. time rate of water vapor transmission through unit area of flat material or Pedestal construction induced by unit vapor pressure A support or base for roof top components difference between two specific surfaces, such as pavers, pipes and small roof top under specified temperature and humidity units. conditions. The English (inch·pound) unit of Peel strength measurement for permeance is gr / h • ft2 • The average load per unit width required to in. Hg, which is commonly referred to as separate progressively a flexible member "perm" units. from a rigid member or another flexible member. pH A measure of the acidity or alkalinity of a Penetration solution, with neutrality represented by a (1) Any construction (e.g., pipes. conduits, value of 7, with increasing acidity represented HVAC supports) passing through the roof; (2) by increasingly smaller values, and with The consistency of a bituminous material increasing alkalinity represented by expressed as the distance, in tenths of a increasingly larger values. millimeter (0.1 mm), that a standard needle penetrates vertically into a sample of material Phased application under specified conditions of loading, time, (1) The installation of a roofing or and temperature. waterproofing system during two or more separate time intervals or different days. Perlite Application of surfacings at different time An aggregate used in lightweight insulating intervals are typically not considered concrete and preformed perlitic insulation phased application. (See Surfacing.) (2) A boards, formed by heating and expanding roofing system not installed in a continuous siliceous volcanic glass. operation.

Perm Picture framing See Permeance. A square or rectangular pattern of ridges in a roof membrane or covering over Permeability insulation or deck joints. (1) The capacity of a porous material to conduct or transmit fluids; (2) The time rate of Pigment vapor transmission through unit area of flat An insoluble compounding material used to material of unit thickness Induced by unit impart color. vapor pressure difference between two specific surfaces, under specified temperature Pinhole and humidity conditions. The English (inch- A tiny hole in a coating, film, foil, membrane pound) unit of measurement for permeability or laminate comparable in size to one made is gr / hr • ft2 • (in. Hg / in.), which is by a pin. commonly referred to as "perm·inch" units. Pipe boot Prefabricated flashing piece used to flash

A1-29 GLOSSARY APPENDIX 1 around circular pipe penetrations. one layer at right angles to the grain of the adjoining layer. Pitch (See Coal tar.) Polychloroprene See Neoprene. Pitch-pocket (Pitch-pan) A flanged, open-bottomed enclosure made of Polyester sheet metal or other material placed around a A polymer in which the repeated structural penetration through the roof, filled with grout unit in the chain is of the ester type. and bituminous or polymeric sealants to seal the area around the penetration. Pittsburgh lock seam Polyisobutylene (PIB) A method of interlocking metal. A product formed by the polymerization of isobutylene. May be compounded for use Plastic cement as a roof membrane material. A roofing industry generic term used to describe asphalt roof cement that is a Polymer trowelable mixture of solvent-based bitumen, A macromolecular material formed by the mineral stabilizers, and other fibers and/or chemical combination of monomers having fillers. Generally, intended for use on either the same or different chemical relatively low slopes, not vertical surfaces. composition. (See Asphalt roof cement and flashing cement.) Polymer modified bitumen (See Modified bitumen.) Plasticizer A material incorporated in a material to Polymeric methylene diphenyl increase its ease of workability, flexibility or diisocyanate (PMDI) distensibility. Component A in SPF. An organic chemical compound having two reactive isocyanate Plasticizer migration groups. It is mixed with the B component to In some thermoplastic roofing membranes, form polyurethane. the loss of plasticizer chemicals from the membrane, resulting in shrinkage and Polymerization embrittlement of the membrane, typically A chemical reaction in which monomers are PVC. linked together to form polymers.

Pliability Polypropylene The material property of being flexible or A polymer prepared by the polymerization moldable. of propylene as the sole monomers.

Ply Polyol A layer of felt or ply sheet in a built-up roof A polyhydric alcohol, i.e., one containing membrane or roof system. three or more hydroxyl groups, one component of polyisocyanurate and Plywood polyurethane compounds. A structural board consisting of an odd number of thin layers of wood glued Polyvinyl chloride (PVC) together under pressure, with the grain of A synthetic thermoplastic polymer prepared

A1-30 GLOSSARY APPENDIX 1

from vinyl chloride. PVC can be Pot life (Working life) compounded into flexible and rigid forms The period of time during which a reacting through the use of plasticizers, stabilizers, composition remains suitable for its intended fillers and other modifiers. Rigid forms are processing after mixing with reaction initiating used in pipes; flexible forms are used in the agents. manufacture of sheeting and roof membrane materials. Pourable sealer A type of sealant often supplied in two parts Polystyrene and used at difficult-to-flash penetrations, A polymer prepared by the polymerization typically in conjunction with pitch-pockets to of styrene as the sole monomer. form a seal.

Pond Press brake A surface that is incompletely drained. A machine used in cold-forming sheet metal or strips of metal into desired profiles. Ponding The excessive accumulation of water at Prestressed concrete low-lying areas on a roof that tend to deflect Concrete in which the reinforcing cables, and attract additional water. wires or rods in the concrete are tensioned before there is load on the structural Pop rivet member, holding the concrete in A relatively small-headed pin with an compression for greater strength. expandable head for joining light-gauge sheet metal. Pre-tinning Coating a metal with solder or tin alloy prior Popcorn surface texture to soldering or brazing it. In SPF roofing, the condition in which the foam surface shows a coarse texture where Primer valleys form sharp angles. This surface is (1) A thin, liquid-applied solvent-based unacceptable for proper coating and bitumen that may be applied to a surface to protection. improve the adhesion of subsequent applications of bitumen; (2) A material that is Positive drainage sometimes used in the process of seaming The drainage condition in which single-ply membranes to prepare the consideration has been made during design surfaces and increase the strength (in shear for all loading deflections of the deck and and peel) of the field splice; (3) A thin liquid- additional roof slope has been provided to applied material that may be applied to the ensure drainage of the roof area within surface of SPVF to improve the adhesion of 48 hours following rainfall during conditions subsequent application of SPVF protective conducive to drying. coatings.

Positive side waterproofing Proportioner An application where the waterproofing The basic pumping unit for SPF or two systems and the source of the hydrostatic component coating systems. Consists of pressure are on the same side of the two positive displacement pumps designed structural element. to dispense two components at a precisely controlled ratio.

A1-31 GLOSSARY APPENDIX 1

Protection course Rafter A sacrificial material used to shield a One of a series of sloped structural members, waterproofing material from damaging that extend from the ridge or hip to the external forces. downslope perimeter or eave, designed to support the roof deck or substructure and its Protection mat associated loads. A sacrificial material used to shield one roof system component from another. Raggle A groove or slot, often cut in a masonry wall Protected membrane roof (PMR) or other vertical surface adjoining a roof, for An insulated and ballasted roofing assembly inserting an inset flashing component such in which the insulation and ballast are as a reglet. applied on top of the membrane (sometimes referred to as an "inverted roof assembly"). Rake The sloped edge of a roof at or adjacent to Psychrometer the first or last rafter. An instrument used to measure humidity in the atmosphere from two thermometers Rake-starter (Bleeder strip) which are similar except that the bulb of one Starter-strip used along rake edges in is kept wet, the bulb of the other being dry. conjunction with asphalt shingle roofing.

Psychrometric chart Re-cover Chart showing the relationship between The addition of a new roof membrane or dew point temperature, dry bulb steepslope roof covering over a major temperature, wet bulb temperature and portion of an existing roof assembly. This relative humidity. process does not involve removal of the existing roofing. Puncture resistance The ability of a material to withstand the Recycle action of a penetrating or puncturing object. The fate of scrap metal roofing material left Purlin over following an install. Horizontal secondary structural member that transfers loads from the roof to the Reflectivity primary structural framing. (See Light reflectance.)

PVC Reglet Polyvinyl chloride. A sheet metal receiver for the attachment of counterflashing. A reglet may be surface- R-value mounted, inset into a raggle or embedded See Thermal resistance. behind cladding.

Racking Reinforced membrane A method of asphalt shingle application, A roofing or waterproofing membrane that also referred to as the straight-up method, has been strengthened by the addition or whereby shingle courses are applied incorporation of one or more reinforcing vertically, up the roof rather than laterally or materials, including woven or nonwoven across and up. glass fibers, polyester mats, or scrims, nylon, or polyethylene sheeting.

A1-32 GLOSSARY APPENDIX 1

Relative humidity (RH) covers the ridge and overlaps the The ratio of the pressure of water vapor intersecting field roofing. present in a given volume of air to the pressure of fully saturated water vapor at Ridge vent the same temperature, expressed as a A ventilator located at the ridge that allows percentage. the escape of warm and/or moist air from the attic area or rafter cavity. Release tape (or Strip) A plastic film or paper strip that is applied to Ridging the back of self-sealing shingles and other (See Buckle.) materials. The strip prevents the material from sticking together in the roll or bundle. Roll materials With asphalt shingles, the strip need not be A general term applied to rolls of roofing removed for application of the shingles. felt, ply sheet, etc., which are typically furnished in rolls. Replacement The practice of removing an existing roof Roll roofing system down to the roof deck and replacing Coated felts, either smooth or mineral- it with a new roofing system. surfaced.

Reroofing Roof The process of re-covering, or tearing-off (1) The cover of a building; (2) To cover and replacing an existing roof system. with a roof.

Retrofitting Roof area divider The installation of an engineered light gage Refer to area divider. steel frame on top of an existing low or steep slope roof on which a new metal roof Roof area expansion Joint is attached. (See Expansion joint.) Roof assembly Resin An assembly of interacting roof components Component B in SPF. This component including the roof deck, vapor retarder (if contains a catalyst, blowing agent, fire present), insulation and roof covering. retardants, surfactants and polyol. It is mixed with the A component to form polyurethane. Roof cement (See Asphalt roof cement or Coal tar roof Ridge cement.) Highest point on the roof, represented by a horizontal line where two roof areas Roof covering intersect, running the length of the area. The exterior roof cover or skin of the roof assembly, consisting of membrane, panels, Ridge cap sheets, shingles, tiles, etc. A material or covering applied over the ridge of a roof. Roof curb Raised frame used to mount mechanical Ridge course units (such as air conditioning or exhaust The last or top course of roofing materials, fans), skylights, etc. on a roof. such as tile, roll roofing, shingles, etc., that

A1-33 GLOSSARY APPENDIX 1

Roof jack large deformations quickly and forcibly. Run: A metal or wood bracket used to support horizontal dimension of a slope. toeboards. (See Flashing collar.) Saddle Roof overhang A small tapered/sloped roof area structure A roof extension beyond the exterior wall of that helps to channel surface water to a building. drains. Frequently located in a valley. A saddle is often constructed like a small hip Roof seamer roof or pyramid with a diamond-shaped (1) Machine that crimps neighboring metal base. (See Cricket.) roof panels together; (2) Machine that welds laps of membrane sheets together Sag using heat, solvent, or dielectric energy. Undesirable excessive flow in material after application to a surface. Roof slope The angle a roof surface makes with the Saturated felt horizontal, expressed as a ratio of the units A felt that has been immersed in hot bitumen; of vertical rise to the units of horizontal the felt adsorbs as much bitumen as it can length (sometimes referred to as run). For retain under the processing conditions, but English units of measurement, when remains porous and contains voids. dimensions are given in inches, slope may be expressed as a ratio of rise to run, such SBS as 4:12 or as an angle. (See Styrene butadiene styrene.)

Roof system Scarfed A system of interacting roof components, Shaped by grinding. generally consisting of a membrane or primary roof covering and roof insulation Screeding (not including the roof deck) designed to The process of striking off excess concrete weatherproof and, sometimes, to improve to bring the top surface of the concrete to the building's thermal resistance. the proper finish and elevation.

Roof walk Screen wall A designated path for pedestrian traffic on a A nonstructural wall erected around units or roof surface in order to provide safety and curbs on a roof. Typically the framing minimize roof damage. Roof walks often consists of girts with a wood or metal include additional non-slip panels and covering attached to the frame. surfaces attached to the roof cladding. Also known as roof walkways, platforms or Scrim crossovers. A woven, nonwoven or knitted fabric composed of continuous strands of material Rosin paper (specifically Rosin-sized used for reinforcing or strengthening sheathing paper) membranes. A nonasphaltic paper used as a sheathing paper or slip sheet in some roof systems. Scupper Drainage device in the form of an outlet Rubber through a wall, parapet wall or raised roof A material that is capable of recovering from edge lined with a soldered sheet metal

A1-34 GLOSSARY APPENDIX 1 sleeve. a self-adhering membrane is protected by a release paper or film, which prevents the Scuttle membrane from bonding to itself during A hatch that provides access to the roof shipping and handling. from the interior of the building. Self-drilling screw Sealant A fastener that drills and taps its own hole (1) A material that has the adhesive and during application. cohesive properties to form a seal; (2) A mixture of polymers, fillers, and pigments Self-sealing shingle used to fill and seal joints where moderate An asphalt shingle containing a factory- movements is expected; unlike caulking, it applied strip or spots of heat sensitive cures to a resilient solid. adhesive intended to adhere the overlying shingle once installed on the roof and Sealant backing warmed by the sun. A compressible material placed in a joint before applying a sealant. Self-tapping screw A fastener that forms receiving threads Sealer when turned in a previously drilled hole. A coating designed to prevent excessive absorption of finish coats into porous surfaces; Selvage a coating designed to prevent bleeding. (1) An edge or edging that differs from the main part of a fabric, granule-surfaced roll Sealing washer roofing or cap sheet, or other material; (2) A A rubber or neoprene washer, sometimes specially defined edge of the material (lined metal-backed, typically placed on a fastener for demarcation), which is designed for to prevent water from migrating into and some special purpose, such as overlapping through the fastener hole. or seaming.

Seam Separator layer A joint formed by mating two separate (See Slip sheet.) sections of material. Seams can be made or sealed in a variety of ways, including folding, Service temperature limits interlocking, adhesive bonding, hot-air The minimum or maximum temperature at welding, solvent welding, using adhesive tape, which a coating, SPF or other material will sealant, etc. perform satisfactorily.

Seam sample Set In single-ply and sometimes modified bitumen To convert into a fixed or hardened state by membrane roofing, a sample from the chemical or physical action. membrane that extends through the side lap of adjacent rolls of membrane, taken for the Shading purpose of assessing the quality of the seam. Slight differences in surfacing color, such as shingle granule coloring, that may occur Self-adhering membrane as a result of manufacturing operations. A membrane that can adhere to a substrate and to itself at overlaps without the use of Shark fin an additional adhesive. The undersurface of An upward-curled felt side lap or end lap.

A1-35 GLOSSARY APPENDIX 1

Shear strength of Units (Le Systeme International d'Unites). The resistance to forces that cause or tend to cause two contiguous parts of a body to Side lap slide relative to each other in a direction A continuous longitudinal overlap of parallel to their contrast. neighboring like materials.

Shed roof Side lap fastener A roof having only one sloping plane and no A fastener used to connect adjacent panels hips, ridges or valleys. together at the side lap.

Shelf life The maximum time a packaged material can Siding be stored under specified conditions and still The finish covering of an exterior wall of a meet the performance requirements frame building; the siding may be a specified. cladding material such as wood, aluminum or vinyl (but not masonry). Shingle (1) A small unit of prepared roofing Sieve designed for installation with similar units in An apparatus with square apertures for overlapping rows or courses on inclines separating sizes of material. normally exceeding 3:12 slope (14°); (2) To cover with shingles; (3) To apply any sheet SiII material in succeeding overlapping rows The bottom horizontal framing member of an like shingles. opening, such as below a window or door.

Shingling Sill flashing (1) The application of shingles; (2) The A flashing of the bottom horizontal framing procedure laying parallel felts so that one member of an opening, such as below a longitudinal edge of each felt overlaps and window or door. the other longitudinal edge underlaps an adjacent felt. Normally felts are shingled on Single-lock standing seam a slope so that water flows over rather than A standing seam that uses one overlapping against each lap. interlock between two seam panels, in contrast with the double interlocking used in Shrinkage a double standing seam. A decrease in one or more dimensions of an object or material. Single-ply membranes Roofing membranes that are field applied Shrinkage crack using just one layer of membrane material In waterproofing, a separation in a material, (either homogeneous or composite) rather such as a concrete substrate, caused by than multiple layers. the inability of the material to resist a reduction in size which occurs during its Single-ply roofing hardening or curing process or both. A roofing system in which the principal roof covering is a single layer flexible membrane SI often thermoset or thermoplastic membrane. An abbreviation for the International System

A1-36 GLOSSARY APPENDIX 1

Skinning Slit sample The formation of a dense film on the In SPF roofing, a small cut about 1 inch x ½ surface of a liquid coating or mastic. inch x ½ inch (25 mm x 13 mm x 13 mm), in a half-moon shape, used to measure Skirt flashing coating film thickness. A formed metal counterflashing secured under a mechanical unit or skylight to cover Slope and protect the upper edge of a base flashing The angle of incline, usually expressed as a and its associated fasteners. ratio of rise to run, or as an angle. (See Roof slope.) Skylight An opening in a roof that is glazed with a Smooth surface texture transparent or translucent material; used to In SPF roofing, the condition of the foam in admit diffused light to the space below. which the surface shows spray undulation and is ideal for receiving a protective coating. Slab on grade A horizontal placement of concrete placed Smooth-surfaced roof directly over a prepared earth substrate. A roof membrane without mineral granule or aggregate surfacing. Slag A hard aggregate that is left as a residue Snap-on cap from blast furnaces, which may be used as A separate cap that snaps on over the a surfacing material on certain (typically vertical legs of some single standing or bituminous) roof membrane systems. batten seam metal roof systems.

Slate Snow guard A hard, brittle metamorphic rock consisting A series of devices attached to the roof in a mainly of clay minerals, used extensively as pattern that attempts to hold snow in place, dimensional stone for steep roofing and in thus preventing sudden snow or ice slides granular form as surfacing on some other from the roof; any device intended to roofing materials. prevent snow from sliding off a roof.

Slating hook Snow load A steep-Slope roofing attachment device, The live load due to the weight of snow on shaped like a hook, that can be used for a roof; included in design calculations. fastening roofing slate. Soffit Slip sheet The exposed undersurface of any exterior Sheet material, such as reinforced kraft overhanging section of a roof eave. paper, rosin-sized paper, polyester scrim or polyethylene sheeting, placed between two Soffit vent components of a roof assembly (such as A premanufactured or custom built air inlet between membrane and insulation or deck) source located at the downslope eave or in to ensure that no adhesion occurs between the soffit of a roof assembly. them and to prevent possible damage from chemical incompatibility, wearing or Softening point abrasion of the membrane. The temperature at which bitumen becomes soft enough to flow, as determined by an

A1-37 GLOSSARY APPENDIX 1 arbitrary, closely defined method (ASTM Spalling Standard test method D 36 or D 3461). Breaking off of plate-like pieces from a concrete, rock or masonry surface. Softening point drift A change in the softening point of bitumen Special steep asphalt during storage or application. (See Fallback) Asphalt complying with ASTM D 312, Type IV. (See Asphalt) Solar reflectance The fraction of solar flux reflected by a Specification surface. A precise statement of a set of requirements to be satisfied by a material, product, system, Solar Reflectance Index (SRI) or service. The relative surface temperature with respect to the standard white (SRI=100) and SPF compound standard black (SRI=0) under standard solar A term used to describe the raw materials and ambient conditions per ASTM E1980. (isocyanate and resin) used to make polyurethane foam. Soli stack A sanitation pipe that penetrates the roof; Splash block used to vent plumbing fixtures. A small masonry or polymeric block laid on the ground or lower roof below the opening Solder of a downspout used to help prevent soil A lead/tin mixture that is melted and used to erosion and aggregate scour in front of the bond two pieces of some types of metals downspout. together. Splice Solid mopping Bonding or joining of overlapping materials. (See Mopping.) (See Seam.)

Solids content Splice plate The percentage by weight of the nonvolatile A metal plate placed underneath the joint matter in an adhesive. between two pieces of metal.

Solvent Splice-tape Any liquid used to dissolve another material. Cured or uncured synthetic rubber tape used for splicing membrane materials. Solvent cleaners Used to clean some single-ply roofing Split membranes prior to splicing, typically including A membrane tear resulting from tensile heptane, hexane, white gasoline, and stresses. unleaded gasoline. Split slab Solvent welding A term used to describe two separate A process where a liquid solvent is used to concrete slabs. The first is placed as a slab chemically weld or join together two or on grade or suspended slab and covered more layers of certain membrane materials with waterproofing and a drainage system. (usually thermoplastic). The second slab, also referred to as a topping slab, is then placed over the

A1-38 GLOSSARY APPENDIX 1 underlying slab and waterproofing. wiping liquid material on, across or off a surface; (2) To smooth, wipe or treat with a Spot mopping squeegee. (See Mopping.) Stainless steel Spray polyurethane foam (SPF) An alloy of steel that contains chromium and A foamed plastic material, formed by also may contain nickel or copper. Generally, spraying two components, PMDI (A has very good resistance to corrosion. component) and a resin (8 component) to form a rigid, fully adhered, water-resistant, Standing seam and insulating membrane. In metal roofing, a type of seam between adjacent sheets of material made by turning Spread coating up the edges of two adjacent metal panels A manufacturing process in which and then folding or interlocking them in a membranes are formed using a liquid variety of ways accommodating for thermal compound that is spread onto a supporting expansion and contraction. reinforcement base layer and then dried to its finished condition. Starter course The first layer of roofing, applied along a line Spreader bar adjacent to the downslope perimeter of the A tool with multiple lift points used with a roof area. With steep-slope water-shedding crane or lift truck in order to safely lift long roof coverings, the starter course is covered bundles of materials. by the first course.

Sprinkle mopping Starter sheets (See Mopping.) (1) Felt, ply sheet or membrane strips that are made or cut to widths narrower than the Spunlaced standard width of the roll and used to start A nonwoven fabric made by mechanically the shingling pattern at an edge of the roof; bonding a dry-laid staple fabric by water jet, (2) Particular width sheets designed for which entangles the individual fibers. perimeters in some mechanically attached and fully adhered single-ply systems. Spud To remove the roofing aggregate and most Starter strip of the bituminous top coating by scraping Roll roofing or shingle strips applied along the and chipping. downslope eave line prior to installation of the first course of roofing and intended to fill Square spaces between cutouts and joints of the first A unit used in measuring roof area equivalent course. to 100 square feet (9.29 m2) of roof area. Static load Square-tab shingles Any load, as on a structure, that does not Shingles with tabs that are all the same size change in magnitude or position with time. and exposure. Steel Squeegee A malleable alloy of iron and carbon (1) A blade of leather or rubber set on a produced by melting and refining pig iron handle and used for spreading, pushing or and/or scrap steel; graded according to the

A1-39 GLOSSARY APPENDIX 1

carbon content (in a range from 0.02 to Strapping (felts) 1.7%); other elements, such as manganese A method of installing roofing rolls or sheet and silicon, may be included to provide good materials parallel with the slope of the special properties. roof.

Steel joist (open web steel joist) Straw nail Normally used as a horizontal supporting A long-shanked nail. Sometimes used for member between beams or other structural fastening over tile at hips and ridges. members, suitable for the support of some roof decks. Stress Steep asphalt The internal resistance of a material to a Asphalt complying with ASTM D 312, Type force, measured as a force per unit area. III. (See Asphalt.) Striations Steep-slope roofs A parallel series of small grooves, channels, A category of roofing that generally include or impressions typically within a metal roof watershedding types of roof coverings panel used to help reduce the potential for oil- installed on slopes exceeding 3:12 canning. (14 degrees). Strip mopping Step flashing (See Mopping.) Individual pieces of sheet metal material used to flash walls, around chimneys, dormers and Strip shingles such projections along the slope of a roof. Asphalt shingles that are manufactured in Individual pieces are overlapped and stepped strips, approximately three times as long as up the vertical surface. they are wide.

Stick Clip Strippable films In waterproofing, a non-penetrating fastener (For metal) added protection of plastic films that is adhered to the waterproofing surface; sometimes applied to coated or finished typically used to retain insulation, drainage metals after the coil coating process. panels, prefabricated protection materials, Applied after prime and top coats to resist etc. against the waterproofing to prevent damage to the finish prior to and during sliding and displacement. shipping, fabrication and installation.

Stiffener rib Stripping or strip-flashing Small intermediate bends in a metal pan Membrane flashing strips used for sealing used to strengthen the panel. or flashing metal flashing flanges into the roof membrane. Stitch fastener A short length fastener used to tack or Stripping in "stitch" thin materials together. Stitch Application of membrane stripping ply or fasteners are not designed for securing plies. cladding securely to a structure. Structural panel Storm anchor A metal roof panel designed to be applied See (See Wind clip.) over open framing rather than a continuous

A1-40 GLOSSARY APPENDIX 1 or closely spaced roof deck. abrasion, dissolution or weathering.

Styrene butadiene rubber Surface texture High molecular weight polymers having The resulting surface from the final pass of rubber-like properties, formed by the random SPF. The following terms are used to copolymerization of styrene and butadiene describe the different SPF surface textures: monomers. smooth orange peel, coarse orange peel, verge of popcorn, popcorn, treebark, and Styrene butadiene styrene copolymer oversprayed. (SBS) High molecular weight polymers that have Surfacing both thermoset and thermoplastic properties, The top layer or layers of a roof covering, formed by the block copolymerization of specified or designed to protect the styrene and butadiene monomers. These underlying roofing from direct exposure to polymers are used as the modifying the weather. compound in SBS polymer modified asphalt roofing membranes to impart rubber- like Surfactant qualities to the asphalt. Contraction for "surface active agent;" a material that improves the emulsifying, Substrate dispersing, spreading, wetting, or other The surface upon which the roofing or surface-modifying properties of liquids. waterproofing membrane is applied (e.g., in roofing, the structural deck or insulation). Swarf Small metal bits and pieces resulting from Substructure cutting and drilling metal panels. Materials and support members beneath roof cladding for the purpose of attaching roofing Synthetic felt materials and transferring loads to the A roof underlayment made from synthetic structure itself. Typical substructures may materials often used in place of asphalt use deck, rafter, or purlin type construction based underlayment. methods. Tab Sump The exposed portion of strip shingles An intentional depression around a roof defined by cutouts. drain or scupper that promotes drainage. Tack-free time Sump pan In SPF-based roofing, a curing phase of A metal pan used to create a depression polyurethane foam to when the material is around a drain or scupper to enhance no longer sticky. When the polyurethane drainage. foam is tack free, it can be sprayed over with another pass, referred to as a "lift". Superimposed loads With some care, the polyurethane foam can Loads that are added to existing loads. For be walked on soon after it is tack free. example, a large stack of insulation boards placed on top of a structural steel deck. Talc Whitish powder applied at the factory to the Surface erosion surface of some roofing materials (e.g., The wearing away of a surface due to vulcanized EPDM membranes), used as a

A1-41 GLOSSARY APPENDIX 1

release agent to prevent adhesion of the Tensile strength membrane to itself. The strength of a material under tension as distinct from torsion, compression or shear. Tapered edge strip A tapered insulation strip used to (1) Elevate Tension leveling and slope the roof at the perimeter and at The process of pulling metal coil stock curbs, and (2) Provide a gradual transition between two spools under a certain from one layer of insulation to another. pressure to help reduce side camber and Taping potential oil canning in the coil stock caused (1) The technique of connecting joints by manufacturing and cutting processes. between insulation boards or deck panels with tape; (2) The technique of using self- Termination adhering tape-like materials to seam or The treatment or method of anchoring and/or splice single-ply membranes. sealing the free edges of the membrane in a roofing or waterproofing system. Tar A brown or black bituminous material, liquid Terne or semisolid in consistency, in which the An alloy of lead and tin, used to coat sheets predominating constituents are bitumens of carbon steel or stainless steel for use as obtained as condensates in the processing metal roofing sheet. of coal, petroleum, oil-shale, wood, or other organic materials. Terra cotta Low-fired clay, either glazed or unglazed. Tar boils Bubbles of moisture vapor encased in a thin Test cut film of bitumen, also known as "blackberries." A sample of the roof system or assembly which exposes the roof deck and is used to Tarred felt diagnose the condition of the membrane, (See Coal tar felt.) evaluate the type and number of plies or number of membranes, or rates of Tear-off and reroof application (e.g., the weight of the average The removal of all roof system components interply bitumen mappings). down to the structural deck, followed by installation of a completely new roof system. Thermal block A compression-resistant insulation block Tear resistance installed between structural steel roof The load required to tear a material, when panels and their supporting members to the stress is concentrated on a small area help maintain insulation R-values and of the material by the introduction of a reduce condensation. prescribed flaw or notch. Expressed in psi (pounds force) per inch width or kN / m Thermal bridge (kilonewton per meter width). The penetration of a material of high thermal conductivity (e.g., a metal Insulation or roof Tear strength membrane fastener) through a material of The maximum force required to tear a low. thermal conductivity (e.g., thermal specimen. insulation); the result is a lowered thermal resistance for the assembly.

A1-42 GLOSSARY APPENDIX 1

Thermal conductance (C) applies to 1 inch (25 mm) thickness of a The time rate of heat flow through a unit specific material. area of a body induced by a unit temperature difference between bodies. In Note 2: It is mathematically incorrect to English (inch-pound) units of measurement, add, multiply, or divide the thermal the number of BTUs that pass through a conductivity (k) value of a material to specified thickness of a one square foot determine the thermal performance value (0.09.m2) sampIe of material in one hour of a different thickness of the same with a temperature difference between the material. If it is necessary to determine two surfaces of 1° F. In English (inch- the thermal performance of a specific pound) units it is expressed as Btu / h•ft2•F. thickness of a material, it is appropriate to convert the thermal conductivity (k) of Note 1: A thermal conductance (C) the material to a thermal resistance (R) value applies to a specific thickness of value (I.e., R = 1/k), and then perform the a specific material or construction. mathematical calculation. Note 2: It is mathematically incorrect to multiply or divide the thermal Thermal contraction conductance (C) value for a specific Dimensional shrinkage of a material due to thickness of a material to determine the a drop in temperature. The amount of thermal conductance value of a different contraction is determined by the amount of thickness of the same material. temperature change, the type of material, and the overall length of the material. Note 3: It is mathematically incorrect to add thermal conductance (C) values to Thermal cycling determine overall thermal performance. If Sequence of values caused by a repetitive it is necessary to determine the overall temperature differential due to changes in thermal performance of a construction, it radiant energy. is appropriate to convert the individual thermal conductance (C) values to Thermal emittance thermal resistance (R) values (i.e., R= The ability of a material to radiate the heat 1/c), and then add the thermal resistance that it absorbs. A surface with a high values (i.e., RT = R1 + R2 + ...). thermal emittance will both absorb heat and radiate heat back into the environment. Thermal conductivity (k) The time rate of heat flow through a unit Thermal expansion area of a homogeneous material in a The increase in the dimension or volume of direction perpendicular to isothermal planes a body due to temperature variations. induced by a unit temperature gradient is called thermal conductivity (k or k-value). In Thermal insulation English (inch-pound) units of measurement, A material applied to reduce the flow of it is the number of BTUs that pass through a heat. See Thermal contraction. 1 inch (25 mm) thickness of a 1 square foot (0.09 m2) sample of material in one hour Thermal movement with a temperature difference between the Changes in dimension of a material as a two surfaces of 1°F. In English (inch-pound) result of temperature changes. units it is expressed as Btu•inch / h•ft2• F. Thermal resistance (R) Note 1: A thermal conductivity (k) value Under steady conditions, thermal resistance

A1-43 GLOSSARY APPENDIX 1

is the mean temperature difference Note 3: Thermal transmittance (U) is the between two defined surfaces of material or reciprocal of the overall thermal construction that induces unit heat flow resistance (RT) of a system (i.e., U = through a unit area. In English (inch·pound) 1/RT). units it is expressed as °F•ft2•h / Btu. Thermography, Infrared Note 1: A thermal resistance (R) See Infrared thermography. value applies to a specific thickness of a material or construction. Thermoplastic Note 2: The thermal resistance (R) of A material that softens when heated and a material is the reciprocal of the hardens when cooled. This process can be thermal conductance (C) of the same repeated provided that the material is not material (i.e., R = 1/C). heated above the point at which decomposition occurs. Note 3: Thermal resistance (R) values can be added, subtracted, multiplied, Thermoplastic olefin membrane (TPO) and divided by mathematically A blend of polypropylene and ethylene- appropriate methods. propylene polymers. Colorant, flame retardants, UV absorbers, and other Thermal shock proprietary substances which may be The stress-producing phenomenon resulting blended with the TPO to achieve the from sudden temperature changes in a roof desired physical properties. The membrane membrane when, for example, a cold rain may or may not be reinforced. shower follows brilliant sunshine. Thermoset Thermal stress A class of polymers that, when cured using Stress introduced by uniform or non- heat, chemical, or other means, changes uniform temperature change in a structure into a substantially infusible and insoluble or material that is contained against material. expansion or contraction. Thinner Thermal transmittance (U or U-factor) (1) A volatile liquid added to an adhesive or The time rate of heat flow per unit area coating material to modify the consistency under steady conditions from the fluid (e.g., or other properties; (2) A liquid used to air) on the warm side of a barrier to the fluid clean equipment or other surfaces. (e.g., air) on the cold side, per unit temperature difference between the fluids. Through-wall flashing In English (inch·pound) units expressed as A water-resistant membrane or material Btu / h•ft2•F. assembly extending totally through a wall and its cavities, positioned to direct water Note 1: A thermal transmittance (U) within the wall to the exterior, usually value applies to the overall thermal through weep holes. performance of a system (e.g., roof assembly). Tie-in In roofing and waterproofing, the Note 2: Thermal transmittance (U) is transitional seal used to terminate a roofing sometimes called the overall coefficient or waterproofing application at the top or of heat transfer. bottom of flashings or by forming a

A1-44 GLOSSARY APPENDIX 1

watertight seal with the substrate, Tuckpointing membrane, or adjacent roofing or The process of removing deteriorated waterproofing system. mortar from an existing masonry joint and troweling new mortar or other filler into the T-joint joint. The condition created by the overlapping intersection of three or four sheets in the U-Value membrane. (See Thermal transmittance.)

Toggle bolt UL label A bolt having a nut with pivoted, flanged An identification label or seal affixed to a wings that close against a spring when it is product or package with the authorization of pushed through a hole, and open after Underwriters Laboratories, Inc. The presence emerging from the hole; used to fasten of the label indicates that the product has met objects to a hollow wall or to a wall which certain performance criteria. is accessible only from one side. Ultraviolet (UV) Tongue and groove planks Invisible light radiation, adjacent to the One of the oldest types of dimensional violet end of the visible spectrum, with structural wood used as roof decking. The wavelengths from about 200 to 400 nm sides are cut with convex and concave (nanometers). grooves so adjacent planks may join in alignment with each other to form a uniform Underlayment roof deck. An asphalt-saturated felt or other sheet material (may be self-adhering) installed Torch-applied between the roof deck and roof covering, Method used in the installation of polymer usually used in a steep-slope roof modified bitumen membranes characterized construction. Underlayment is primarily by using open flame propane torch used to separate the roof covering from the equipment. roof deck, shed water and provide secondary weather protection for the roof Traffic bearing area of the building. In waterproofing, a membrane formulated to withstand a predetermined amount of Underwriters Laboratories, Inc. (UL) pedestrian or vehicular traffic with separate An organization that tests, rates, and protection and a wear course. classifies roof assemblies for their resistance to fire, impact, leakage, corrosion of metal Transverse seam components, and wind uplift. The joint between the top of one metal roof panel and the bottom of the next panel, Uplift which runs perpendicular to the roof slope. See Wind uplift.

Treebark surface texture Valley In SPF roofing, the surface condition of the The internal angle formed by the foam which shows a coarse texture where intersection of two sloping roof planes. valleys form sharp angles. This surface is unacceptable for proper coating and Vapor migration protection. The movement of water vapor from a region

A1-45 GLOSSARY APPENDIX 1 of high vapor pressure to a region of lower stress. For bitumen, measured in vapor pressure. centipoise. (See Viscous.)

Vapor pressure Viscous The pressure exerted by a vapor of a solid Resistant to flow under stress. or liquid when in equilibrium with the liquid or solid. Void An open space or break in consistency. Vapor retarder A layer(s) of material or a laminate used to Volatile appreciably reduce the flow of water vapor A relative term expressing the tendency to into a roof assembly. form vapor.

Veneer Volatile organic compounds (VOC) (1) A single wythe of masonry for facing Means any compound of carbon, excluding purposes that may not be structurally carbon monoxide, carbon dioxide, carbonic connected; (2) Any of the thin layers of acid, metallic carbides or carbonates, and wood glued together to form plywood. ammonium carbonate, which participate in atmospheric photochemical reactions. Vent An opening designed to convey air, heat, water vapor or gas from inside a building or Vulcanization a building component to the atmosphere. An irreversible process during which a rubber compound, through a change in its Ventilator chemical structure (for example, cross- An accessory that is designed to allow for linking), becomes less plastic and more the passage of air. resistant to swelling by organic liquids and elastic properties are conferred, improved, Verge of popcorn texture or extended over a greater range of In SPF roofing, the roughest texture temperature. suitable for receiving the protective coating on a sprayed polyurethane foam roof. The Warm roof assembly surface shows a texture where nodules are A roof assembly configured with each larger than valleys, with the valleys component placed immediately on top of relatively cured. This surface is acceptable the preceding component; each component for receiving a protective coating only is in contact with the adjacent component. because of the relatively cured valleys. The No space is provided for ventilation of the surface is considered undesirable because roof assembly. Also known as a "compact" of the additional amount of coating material roof assembly. required to protect the surface properly. Wash coat Vermiculite A primer, typically provided on the back side An aggregate used in lightweight insulating of painted metal products to help protect the concrete, formed by heating and expanding underlying metal from wear and corrosion. of a micaceous material. Water cure Viscosity A method of curing a material, such as The resistance of a material to flow under concrete, by applying a fine mist of water

A1-46 GLOSSARY APPENDIX 1

over the surface to control the rate of Weep holes moisture evaporation from the material. Small openings whose purpose is to permit drainage of water that accumulates inside a Water cutoff building component (e.g., a brick wall, skylight (See Cutoff.) frame, etc.).

Water-shedding Weld The ability of individual, overlapping To join pieces of metal together by heat components to resist the passage of water fusion. without hydrostatic pressure. Water stop Wet A diaphragm used across a joint as a sealant, A condition where free water is present in usually to prevent the passage of water. or on a substance.

Water table Wet bulb temperature The level within the ground, below which The temperature of air as registered by a the soil is saturated with water. thermometer whose bulb is covered by a water wetted wick. Water vapor transmission A measure of the rate of transmission of Wet film thickness water vapor through a material under The thickness, expressed in mils, of a controlled laboratory conditions of coating or mastic as applied but not cured. temperature and humidity. Customary units For comparison, see Dry film thickness. are grains / h•ft2. Wicking Waterproof The process of moisture movement by The quality of a membrane, membrane capillary action. material, or other component to prevent water entry. Wind clip A steep-slope roofing attachment device Waterproofing that fits over the butt end of tile, slate, and Treatment of a surface or structure to prevent stone to help secure individual roofing units the passage of water under hydrostatic from wind uplift. pressure. Wind load Wear Course Force exerted by the wind on a structure or The top layer of surfacing that carries part of a structure. pedestrian or vehicular traffic. Sometimes referred to as wearing surface. Wind uplift The pressure caused by the flow of wind at Wearing Surface roof edges, roof peaks or obstructions, (See Wear course.) causing a drop in air pressure immediately above the roof surface. Weatherproof The ability of a membrane or roof covering Wire tie system to prevent the passage of water with a A system of attachment for steep-slope limited amount of hydrostatic pressure. roofing units (e.g., tile, slate and stone) using fasteners (nails and/or screws) in

A1-47 GLOSSARY APPENDIX 1 conjunction with wire to provide a concealed fastening system.

Work slab See Mud slab.

Woven valley A method of valley construction in which shingles or roofing from both sides of the valley extend across the valley and are woven together by overlapping alternate courses as they are applied.

Wythe A masonry wall, one masonry unit, a minimum of two inches thick.

Yield The point where a material no longer returns to its original state, form, or shape.

Zee section A member formed in the shape of the letter "Z' from coiled steel stock.

Zinc A hard bluish white metal, brittle at normal temperatures, very malleable and ductile when heated; not subject to corrosion; used for galvanizing sheet steel and iron, in various metal alloys, and as an oxide for white paint pigment.

A1-48 ABBREVIATIONS AND ACRONYMS APPENDIX 2

°F BUR Degrees Fahrenheit Built-up Roof

AAMA c or c value American Architectural Manufacturers Thermal Conductance Association (expressed as Btu / h•ft2•F)

ALC CABO Air Leakage Control Council of American Building Officials

ANSI CERL American National Standards Institute Construction Engineering Research Laboratory APA American Plywood Association cfm Cubic Feet per Minute (also CFM) APC American Plastics Council CFR Code of Federal Regulations APP Atactic polypropylene CPA copolymer alloy APC/SPFA American Plastics Council / Spray CPE Polyurethane Foam Alliance Chlorinated polyethylene

ARMA CPSC Asphalt Roofing Manufacturers Association Consumer Products Safety Commission

ASHRAE CRREL American Society of Heating, Refrigerating Cold Regions Research and Engineering and Air-Conditioning Engineers Laboratory

ASME CSA American Society of Mechanical Engineers Canadian Standards Association

AZ50 CSM 0.50 oz/sq. ft. (150 g/sq. m.) Chlorosulfonated polyethylene coated Galvalume sheet CSPE BOCA Chlorosulfonated polyethylene Building Officials and Code Administrators, International, Inc. DOE (United States) Department of Energy BTU British Thermal Unit DP Design Pressure

A2-1 ABBREVIATIONS AND ACRONYMS APPENDIX 2

ECH HVAC Polyepichlorohydrin, commonly referred to Heating Ventilation and Air Conditioning as epichlorohydrin IBC EIFS International Building Code Exterior Insulation and Finish System ICBO International Conference of Building EIP Officials Ethylene interpolymer ICC EMC International Code Council Equilibrium moisture content IGMA EPA Insulating Glass Manufacturers Alliance Environmental Protection Agency IN. EPDM Inch, inches, or double quote " Ethylene propylene dlene terpolymer IRC EVT International Residential Code Equiviscous temperature IRMA™ FM Inverted roof membrane assembly Factory Mutual (Research Corporation) ISANTA FMR International Staple, Nail & Tool Factory Mutual Research (Corporation) Association

FPL IWC Forest Products Laboratory Inches of Water Column (also iwc)

FRT k or k value Fire retardant treated Thermal conductivity (expressed as Btu•inch / h•ft2 • 0 F) F.S. Federal Specifications KSI Kilopounds per square inch FT. Foot, feet, or single quote ' MBMA Metal Building Manufacturers Association G90 0.90 ounce Galvanized metal sheet MCA Metal Construction Association GANA Glass Association of North America MRA Metal Roofing Alliance GFRC Glass Fiber Reinforced Concrete

A2-2 ABBREVIATIONS AND ACRONYMS APPENDIX 2

MSDS PMDI Material Safety Data Sheet Polymeric methylene diphenyl diisocyanate

N PMR Newton Protected membrane roof

NBP psf Commonly referred to as nitrile butadiene Pounds per Square Foot copolymer PVC NDT Polyvinyl chloride Nondestructive testing R NHD Thermal resistance Nuclear hydrogen detection (expressed as °F•ft2•h / Btu) RH NFPA Relative humidity National Fire Protection Association SBCCI NFRC Southern Building Code Conference National Fenestration Rating Council International

NIST SBS National Institute of Standards and Styrene butadiene styrene Technology SI NRCA International System of Units (Le Systeme National Roofing Contractors Association International d'Unites)

O.C. SMACNA On Center Sheet Metal and Air Conditioning Contractors National Association ORNL Oak Ridge National Laboratory SPF Spray polyurethane foam. OSHA Occupational Safety and Health SPFA Administration Sprayed Polyurethane Foam Alliance (a business unit of the American Plastics Pa Council) Pascal (unit of pressure) U or U factor PG Thermal transmittance Performance Grade (expressed as Btu / h•ft2•F)

PIB UBC Polyisobutylene Uniform Building Code

A2-3 ABBREVIATIONS AND ACRONYMS APPENDIX 2

UL Underwriters Laboratories

UV Ultraviolet

VOC Volatile organic compounds

WDMA Window and Door Manufacturers Association (formerly NWWDA)

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