Roofing Glossary

Roof Covering: shingles, tile, slate or metal and underlayment that protect the sheathing from weather.

Sheathing: plywood or sheet material that are fastened to roof rafters to cover a house or building

Roof structure: rafters and trusses constructed to support the sheathing

Flashing: pieces of metal used to prevent water seepage around any intersection or projection in a roof system, such as vent pipes, chimneys, valleys and joints

Drainage: a roof system’s design features such as shape, slope and layout that affect its ability to shed water

Dormer: a small structure projecting from a sloped roof, usually with a window

Drip Edge: an L shaped strip (usually metal) installed along roof edges to allow water run off

Eave: the horizontal lower edge of a sloped roof

Fascia: a flat board, band or face located at a cornices outer edge.

Louvers: Slatted devices installed in a gable or soffit (the underside of eaves) to ventilate the space below a roof deck and equalize air temperature and moisture

Square: the common measurement for roof area. One square is 100 square feet (10 by10 feet).

Truss: engineered components that supplement rafters in many newer homes and buildings. Trusses are designed for specific applications and cannot be cut or altered.

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