Glossary Of Roofing Terms


Rooftop fungus that can  leave dark stains on roofing


Asphalt is a sticky, black and highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product; it is a substance classed as a pitch.


Asphalt Roofing Manufacturers Association is an organization of asphalt roofing manufacturers.

Asphalt Primer

Asphalt-based primer used to prepare the surface of concrete, metal, or other materials to enhance the adhesion of asphalt adhesives or asphalt sealant.  Meets ASTM D41. 

Air Barrier

The assembly of materials used in building construction to reduce or slow the passage of air into and out of the building.

Angled Fasteners

Roofing nails and staples driven into decks at an angle – not perpendicular to the roof deck surface. 

APA: The Engineered Wood Association

The APA: The Engineered Wood Association is a trade organization that develops product standards, installation standards, and does certification testing of engineered wood products such as plywood and OSB (oriented strand board).

Asphalt Plastic Cement

A solvent-based asphalt sealant used for hand sealing shingles and sealing other locations on asphalt roofs.  Meets ASTM D4586 Type I or II.

Apron Flashing

Metal flashing used at chimney or dormer fronts.


ASTM International (formerly The American Society for Testing and Materials), an organization that develops and publishes voluntary consensus standards, test methods, and specifications for a wide variety of materials, including roofing.
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