Roofing Terms

Before you hire a roofing contractor to work on your home or business, you should at least have the roofing know-how to know-what you’re talking about (or at least sound like it). Don’t go into your next home improvement or repair project blind. First, familiarize yourself with this beginner’s glossary of basic roofing terminology.

Accumulated Snow: A particular problem during the Rochester deep freeze, heavy snow build up can cause cracks in your roof, which in turn leads to leaks and costly water damage.

Algae: Rooftop fungus that can leave ugly stains on roofs.

Angie’s List: An online directory where consumers can research reviews and testimonials on contractors in their area. Because Angie’s List does not allow anonymous reviews, it is generally considered far more reliable than sites like Yelp.

Asphalt Shingle: The most common roofing material in North America because of their relatively low installation cost. Asphalt shingles come in various types to help them survive water, fire damage, and inclement weather, like snow, wind, and hail.

ASTM: The American Society for Testing and Materials, which sets standards for roofing materials.

Bitumen, Bituminous: Basically another word for asphalt, bitumen is an organic tar-like substance used in many construction materials.

Cupping: When shingles on an existing roof curl or “cup” due to improper installation, over exposure, or a manufacturing defect.

Drip Edge: A strip of metal material placed along the edges of a roof to stop water from dripping onto the eaves, siding, deck (or people!) below.

Dormer: A small structure with windows that sticks out from the slant of the roof.

Eaves: the edges of a roof that meet or overhang the walls of a home or building. Generally, the three feet of a roof closest to the edge.

Flashing: Waterproof material placed around projections like chimneys, pipes, or vents. An area where the flashing is covered by shingles is called a “closed valley.”

Gable Roof: A traditional building design, where two peaked roof planes meet to form a single line.

Granules: The crushed rock and ceramic coating that is used on the surface of most roofing shingles.

Hand Sealing: For steep roofs, or homes in cold weather areas (like Rochester), it may be necessary for contractors to seal shingles by hand.

Hip Roof: A roof with four separate roof planes that come together to form a pyramid. If a child drew a roof on a house, this is what it would look like.

Ice Dams: The bane of Rochester roofs for centuries, ice dams form when melting snow re-freezes near the roof overhang. Ice dams cause snow melt to form a reservoir and can cause leaks and water damage.

Interlocking Shingles: Shingles that fit together to provide wind resistance.

Laminated Shingles: Also known as “Architectural” or “Dimensional Shingles.” Shingles made from two pieces laminated together.

Mansard Roof: A four-sided roof joined by a flat plane surface on top. Mansard roofs often feature Dormers as well.

Membrane: Waterproofing material usually installed on flat roof surfaces to prevent leaks and water build up.

Roofing Contractor: Sometimes called a “roof mechanics,” a roofing contractor is a company or construction worker that specializes in roof installation, repair, or waterproofing.

Subcontractor:A worker hired by a general contractor to perform tasks as part of a larger project. Always ask your contractor if they plan to subcontract any work on your home or building.

Self-Sealant: Sealant that is activated by the sun and heat after installation.

Soffit Ventilation: Ventilation area installed under the eaves.

Valley: The area where two roof planes intersect and form a “V” shape.

Witch Window: also known as “lazy windows,” these oddities are peculiar to American architecture and are most popular in the Northeast, particularly in or near Vermont. These windows are tilted diagonally 45 degrees, so they’re parallel to the roof slope. Witch windows allow a builder to fit a full window into a narrow space between two roof lines. According to urban legend, they’re called Witch windows because it would be difficult for a witch to fly through the tilted design.