International Conference of Building Officials.
A mass of ice formed at the transition from a warm to a cold roof surface, frequently formed by refreezing meltwater at the overhang of a steep roof, causing ice and water to back up under roofing materials.
A continuous membrane installed under steep slope roofing materials in areas subject to ice damming that prohibits water which gets through the roof covering from getting into the structure. Must also seal the fasteners that penetrates it.
The lowest temperature at which combustion will occur spontaneously under specific conditions.
Resistance to fracture under the sudden application of an exerted force.
In roofing materials manufacture, to completely surround the fibers in a felt or mat with bitumen, with the spaces between the fibers partially or completely filled without a continuous coating of bitumen on the surface.
Thermal resistance value established under installed conditions and measured over the expected service life of the material.
The process of displaying variations of apparent temperatures (variation of temperature or emissivity or both) over the surface of an object by measuring variations in infrared radiance.
Being or composed of materials other than hydrocarbons and their derivatives, or matter that is not of plant or animal origin.
Wire mesh used to prevent insects from entering the building through ventilators, louvers, or other openings.
The fresh air that is drawn into a passive ventilation system through vents typically installed in the soffit or eave of a roof.
A felt, metal, or membrane sheet material used between courses of steep-slope roofing to improve the weather- and water-shedding characteristics of the primary roof covering during times of wind-driven precipitation. Typically used with wood shakes.
Individual shingles that mechanically attach to each other to provide enhanced wind resistance without reliance on sealing strips.
A patented, proprietary variation of the “protected membrane roof assembly” in which Styrofoam® brand insulation and ballast are placed over the roof membrane. IRMA™ and Styrofoam® are registered trademarks of the Dow Chemical Company.
International Staple, Nail & Tool Association
A highly reactive organic chemical containing one or more isocyanate (-N=C=0) groups. A basic component in SPF based systems and some polyurethane coating systems.