Term Description

Copolymer alloy.


A nonlinear separation or fracture occurring in a material.


In coatings, visible breaks in the film thickness that extend to the surface and the previously applied coating or substrate.


Fine, random cracks forming a network on the surface of a membrane, coating or film.

Cream time

Time in seconds (at a given temperature) when the A and B components of polyurethane foam will begin to expand after being mixed; recognizable as a change in color of the materials.


The time-dependent part of a strain resulting from stress.


A construction to divert water around or away from a chimney, wall, expansion joint or other penetration.


Cold Regions Research and Engineering Laboratory.

Crushed stone

The product resulting from the artificial crushing of rocks, boulders or large cobblestones, substantially all faces of which have resulted from the crushing operation.


Construction Specifications Institute.


See "chlorosulfonated polyethylene."


(1) A raised member used to support roof and waterproofing penetrations, such as skylights, mechanical equipment, hatches, etc., above the level of the roof or waterproofing surface; (2) a raised roof or waterproofing perimeter relatively low in height.


A process whereby a material is caused to form permanent molecular linkages by exposure to chemicals, heat, pressure and/or weathering.

Cure time

The time required for a material to reach its desirable long-term physical characteristics.

Cured concrete

Concrete that has attained its intended design performance properties.

Curing agent

An additive in a coating or adhesive that results in increased chemical activity between the components with an increase or decrease in rate of cure.

Curing compound

A liquid that is sprayed or otherwise applied to newly placed concrete to retard the loss of water during curing.


Solvent-thinned bitumen used in cold-process roof adhesives, roof cements and roof coatings.


A permanent detail designed to prevent lateral water movement in an insulation system and used to isolate sections of a roof system. (A cutoff is different from a tie-in, which may be a temporary or permanent seal.) See "tie-in."


The open portions of a strip shingle between the tabs; sometimes referred to as a "keyway."

Dead level

Absolutely horizontal or zero slope. See "slope."

Dead load

The weight of a structure itself, including the weight of fixtures or equipment permanently attached to it.

Dead-level asphalt

See "asphalt, dead-level."


A structural component of the roof of a building. The deck must be capable of safely supporting the design dead and live loads, including the weight of the roof or waterproofing system, and the additional live loads required by the governing building codes and provide the substrate to which the roof or waterproofing system is applied. Decks are either noncombustible, (e.g., corrugated metal, concrete or gypsum) or combustible (e.g., wood plank or plywood).

Deflection (bowing, sagging)

(1) The deformation of a structural member as a result of loads acting on it; (2) any displacement in a body from its static position or from an established direction or plane as a result of forces acting on the body.