Roofing Glossary

Roofing Terminology

Understanding roofing can feel overwhelming at first, especially when you’re hearing unfamiliar roof terms and detailed roof structure terminology during a repair or replacement project. That’s why we created this straightforward roofing glossary. Whether you’re getting ready for a roof inspection, talking with a contractor, or simply trying to learn the basics, Tridom Roofing is here to help you feel confident. From common roof terminology to complex roof structure terms, this guide breaks it all down in plain language—no experience needed.

Roof Asphalt-Shingles are a popular, affordable roofing material made from asphalt-coated fiberglass.

A roof cricket is a raised ridge structure that diverts water around chimneys or other roof penetrations to prevent pooling.

Roof Decking is the wood base layer that supports roofing materials.

A roof Dormer is a roofed window structure that adds light, space, and charm. 

A downspout is a vertical pipe that directs rainwater from the gutter to the ground or drainage system.

The roof Drip-Edge is a metal flashing that directs water into gutters.

A roof Eave is the roof edges that overhang the walls for water protection and shading.

Roof Fascia is the board that caps the ends of rafters and supports the gutters. 

Roof Flashing is the waterproof material around joints to prevent leaks. 

A roof Gable is the triangular wall section under a pitched roof. 

A hip rafter is a diagonal rafter that forms the intersection where two roof slopes meet at an external angle.

A roof Ice-Dam is the winter buildup of ice at the eaves that causes roof leaks. 

An inverted roof is a roofing system where the insulation layer is placed above the waterproof membrane, protecting it from temperature fluctuations and physical damage.

A roof overhang is the portion of the roof that extends beyond the exterior walls, providing shade and protection from the elements.

A roof Ridge is the highest horizontal line where two roof slopes meet. 


Roof run is the horizontal distance covered by one side of a roof from the eave to the ridge.

Roof rise is the vertical distance from the top of the wall plate to the ridge of the roof.

A roof reglet is a groove cut into a wall or mortar joint to receive flashing, providing a seal between the roof and vertical surfaces.

A roof rake is the inclined edge of a roof that runs from the eave to the ridge, typically on gable ends.

Reroofing is the process of installing a new roof covering over an existing roof without removing the old materials.

A roof rafter is a sloped structural beam extending from the ridge to the eaves, supporting the roof deck and covering.

A roof Ridge-Vent is the vent along the ridge for attic ventilation. 

Roof sheathing is the layer of boards or panels that forms the base layer of the roof, supporting shingles or other roofing materials.

A roof Soffit is the panel covering the underside of eaves, often ventilated. 

Roof slope is the angle or steepness of a roof, typically expressed as a ratio of vertical rise to horizontal run.

A roof Truss is the engineered framework that supports the roof. 

Roof Underlayment is the protective barrier installed under shingles.

A roof Valley is the area where two roof slopes meet and channel water runoff.

A roof vent is an opening or device installed in the roof to allow air circulation, helping to regulate temperature and moisture levels in the attic.