Glossary

Major Components of a Roof

Built-up Roof A low-slope or flat roof covered with alternating layers of roofing felt and hot-mopped asphalt and topped off with a layer of gravel.

Cornice The wood or metal finishing at ends or edges of building, including a fascia, frieze, or rake.

Counter Flashing The flashing that is embedded, or attached, and sealed at its top in a wall or other vertical structure and is lapped down over base flashing. Courses Horizontal rows of shingles or tiles

Drip Edge The strip of metal extending out beyond the eaves or rakes to prevent rainwater from curling around the shingles back into the wooden portion of the house.

Eaves The lower edge of a roof (often overhanging beyond the edge of the house).

Eave, Ice, and Snow Guard A 3-foot wide rubber membrane adhered to the sheathing at the roof’s edge that attempts to stop migrating water from entering your home during severe ice dams.

EPDM A synthetic rubber membrane (ethylene propylene diene monomer), used on low-slope and flat roofs.

Felt The bituminous paper used by roofers, usually made of a combination of asphalt and either paper or rags.

Fascia A decorative board extending down from the roof edge either at the eave or at the rake.

Flashing Sheet metal or other material used at various planes on a roof to prevent water leakage.

Frieze Board A board at the top of the house’s finished wall, forming a corner with the soffit.

Laced Valley A laced valley, or woven valley, is a continuous run of shingles where two sloping roofs meet.

Rafter Structural wood, usually slanted, to which sheathing is attached.

Rake The slanting edge of a gable roof at the end wall of the house.

Ridge The horizontal line at the top edge of two sloping roof planes.

Sheathing Boards or sheet material that are nailed to the rafters to which shingles or other outside roofing materials are secured.

Shingle Flashing Flashing that is laid in strips under each shingle and bent up at the edge of a chimney or wall.

Pitch (slope) The number of inches of vertical rise in a roof per 12-inches of horizontal distance.

Soffit The area that encloses the underside of that portion of the roof that extends out beyond the sidewalls of the house.

Square One hundred square feet of roof or the amount of roofing material needed to cover 100 square feet when properly applied.

Underlayment The material (usually roofing felt) laid on top of sheathing before shingles are applied.

Valley Where two sloping roof sections come together. Shingles in the valley are cut in a “V” direction exposing the valley flashing fabric.

Valley Flashing The metal or fabric in valleys, extending in under the shingles on both sides.