Glossary Of Terms
Roofing, Waterproofing & Dampproofing
ASPHALT: a dark brown to black cementitious material in which the predominating constituents are bitumens, which occur in nature or are obtained in petroleum processing.
ASPHALT, AIR BLOWN: an asphalt produced by blowing air through molten asphalt at an elevated temperature to raise its softening point, and modify other properties.
BITUMEN: the generic term for an amorphous, semi-solid mixture of complex hydrocarbons derived from any organic source. Asphalt and coal tar are the two bitumens used in the roofing industry.
BITUMINOUS EMULSION: (1) a suspension of minute globules of bituminous material in water or in an aqueous solution; (2) a suspension of minute globules of water or an aqueous solution in a liquid bituminous material (invert emulsion).
BOND: the adhesive and cohesive forces holding two roofing components in intimate contact.
COAL TAR BITUMEN: a dark brown to black, semi-solid hydrocarbon formed as a residue from the partial evaporation or distillation of coal tar. It is used as the waterproofing agent in dead-level or low-slope built-up roofs. It differs from COAL TAR PITCH in having a lower from-end volatility. (For specification properties,see ASTM Standard D 450, Type III.)
COAL TAR PITCH: a dark brown to black, semi-solid hydrocarbon formed as a residue from the partial evaporation or distillation of coal tar. It is used as the waterproofing agent in dead-level or low-slope built-roofs. (For specification properties, see ASTM Standard D 450, Types I II and III).
CONDENSATION: the conversion of water vapor or other gas to liquid as the temperature drops or the atmospheric pressure rises. (See DEW-POINT.)
CUTBACK: any bituminous roofing material that has been solvent thinned. Cutbacks are used in cold-process roofing adhesives, flashing cements, and roof coatings.
DAMPPROOFING: treatment of a surface or structure to resist the passage of water in the absence of hydrostatic pressure.
DEAD LEVEL ASPHALT: a roofing asphalt that has a softening point of 140Â°F (60Â°C) and that conforms to the requirements of ASTM Standard D-312, Type 1.
DEW-POINT: the temperature at which water vapor starts to condense in cooling air at the existing atmospheric pressure and vapor content.
ELASTOMER: a macromolecular material that returns rapidly to its approximate initial dimensions and shape after substantial deformation by a weak stress and the subsequent release of that stress.
ELASTOMERIC: the term used to describe the elastic, rubber-like properties of a material.
EMBEDMENT: (1) the process of pressing a felt, aggregate, fabric, mat, or panel uniformly and completely into hot bitumen or adhesive; (2) the process of placing a material into another material so that it becomes an integral part of the whole material.
FABRIC: a woven or non-woven cloth of organic or inorganic filaments, threads or yarns.
FLASHING: the system used to seal the edges of a membrane at walls, expansion joints, drains, gravel stops, and other areas where the membrane is interrupted or terminated. Base flashing covers the edges of the membrane. Cap flashing or counterflashing shields the upper edges of the base flashing.
FLASHING CEMENT: a trowelable mixture of cutback bitumen and mineral stabilizers, including or other inorganic fibers.
FLAT ASPHALT: a roofing asphalt that has a softening point of approximately 170Â°F (77Â°C) and that conforms to the requirements of ASTM Standard D-312, Type II.
FLUID APPLIED-ELASTOMER: an elastomeric material, which is fluid at ambient temperature, that dries or cures after application to form a continuous membrane.
MEMBRANE: a flexible or semi-flexible roof covering or waterproofing layer, whose primary function is the exclusion of water.
POND: a roof surface which is incompletely drained.
PRIMER: a thin, liquid bitumen applied to a surface to improve the adhesion of subsequent applications of bitumen or other coatings.
SEALANT: a mixture of polymers, fillers, and pigments used to fill and seal joints where moderate movement is expected; it cures to a resilient solid.
SOFTENING POINT: the temperature at which bitumen becomes soft enough to flow. The softening point of asphalt is measured by the "ring-and-ball" test (ASTM Standard D 2398). The softening point of coal tar pitch is measured by the "cube-in-water" test (ASTM Standard D 61).
TAR: a brown or black bituminous material, liquid or semi-solid in consistency, in which the predominating constituents are bitumens obtained as condensates in the processing of coal, petroleum, oil-shale, wood, or other organic materials.
WATERPROOFING: is the treatment of a surface to prevent the passage of water under hydrostatic pressure.