Roofing Terms

Common Roofing Terms Glossary

As Roofing contractors it’s our job to know not only roofs but our roofing products backwards and forwards. Occasionally some of the terminology being used can leave homeowners out of the loop, but with the brief glossary of common terms below we hope to shine some light on words and phrases common to roofers and in turn keep you educated as the homeowner.

-Angled Fasteners: Nails and staples applied to the roof at non parallel angles to the wood surface the roofing material is being applied to.

-Blistering: Bubbles and bumps in damaged roofing materials that are usually caused by excess moisture trapped either under the material or trapped inside and trying to evaporate.

-Cupping: Shingles that have not been installed correctly over the original roof can over time form a curl or cup. Occasionally the curling can be caused by defective shingles.

-Deck: This refers to the surface the roofing material is applied to, and is usually some form of plywood or planking.

-Dormer: A structure which commonly contains a window coming out of the surface of a sloped roof.

-Exposure: Any area that roofing material will be exposed to weather over time.

-Flashing: Waterproofing material applied around any projections.

-Fire Rating: A ranking system designed to illustrate the fire resistance of any roofing material. Fire resistance is on a letter grading system of A, B, or C.

-Granules: Crushed rock that is treated using a special ceramic and chemical mixture that is then used as the top coat on a shingle.

-High Nailing: This refers to shingles that are nailed higher than recommended. Depending on the type of shingle high nailing can be detrimental to the longevity of the roof.

-Ice Dam: This happens when snow partially melts and refreezes in an area of the roof that forces water to be backed up for extended periods of time.

-Laps: Where roofing rolls and underlayments overlap each other.

-Mats: The base material that other roofing material is laid on top of.

-Nesting: Refers to the process of aligned new shingles with the original roof to avoid curling or cupping.

-Overdriven: Fasteners that are driven so hard into the roofing material that it causes damage.

-Penetrations: Refers to any projection coming out of the roof surface. This could be vents, chimney stacks, skylights and piping.

-Quarter Sized: The ideal size for sealant application.

-Racking: An installation technique that involves systematically laying shingles straight up the roof.

-Rafters: The skeleton or support framing onto which the roof decking material is applied.

-Self Sealant: Refers to a shingle sealant that is activated by heat and sunlight.

-Transitions: When a roof plane transitions into another pitch and slope.

-Truss: A truss is a prefabricated wood component that supplements rafters in newer construction projects. Trussed are designed using specific measurements and are not altered once they get to the job sight.

-Underdriven: Fasteners that are not pushed far enough into the surface of the shingle.

-Vapor: Refers to an over abundance of humidity in the air.

-Woven Valleys: When shingles intersect each other in a criss-cross pattern up a roof valley.