Roofing Glossary

Here are some words and phrases you might hear during your roof replacement process.

Allow us to explain them for you!

Algae Discoloration

A type of roof discoloration caused by algae. Commonly described incorrectly as fungus growth.


Bubbles that may appear on the surface of asphalt roofing after installation. 


The surface, installed over the supporting framing members, to which the roofing material is applied.

Drip Edge

A corrosion-resistant, non-staining material used along the eaves and rakes to allow water run-off to drip clear of underlying construction.


The horizontal, lower edge of a sloped roof.


Fibrous material saturated with asphalt and used as an underlayment or sheathing paper.


Pieces of metal used to prevent seepage of water into a building around any intersection or projection in a roof such as vent pipes, chimneys, adjoining walls, dormers and valleys. 


The upper triangular portion of a sidewall that comes to a point at the ridge of a double sloping roof. 


The inclined external angle formed by the intersection of two sloping roof planes. Runs from the ridge to the eaves.


The inclined edge of a sloped roof over a wall.


The uppermost, horizontal external angle formed by the intersection of two sloping roof planes.


The horizontal distance from the eaves to a point directly under the ridge. 


The degree of roof incline expressed as the ratio of the rise, in inches, to the run, in inches. For example, a roof slope of 4/12 has a 4 inch rise every 12 inches.


A unit of roof measure covering 100 square feet

Step Flashing

Base flashing application method used where a vertical surface meets a sloping roof plane.


The exposed portion of strip shingles defined by cutouts.


Asphalt saturated felt or specially engineered synthetic material used beneath roofing to provide additional protection for the decking.


The internal angle formed by the intersection of two sloping roof planes.


Any outlet for air that protrudes through the roof deck such as a pipe or stack. Any device installed on the roof, gable or soffit for the purpose of ventilating the underside of the roof deck.