Edmonds Roofing Contractor

Glossary

O

Open soffit

Underside of an overhang that is not finished.

Open valley

Method of valley construction in which shingles on both sides of the valley are trimmed along a chalk line snapped on each side of the valley. Shingles do not extend across the valley. Valley flashing is exposed.

Organic felt

An asphalt roofing base material manufactured from cellulose fibers and asphalt bitumen.

Organic shingle

An asphalt shingle reinforced with organic material manufactured from cellulose fibers and asphalt bitumen.

OSB

Oriented strand board (OSB) is cheaper than plywood, but not as strong as plywood, and does not hold nails as well as plywood. One side has a slip resistant coating and should be placed facing up.

OSB sheeting

Oriented strand board. Directionally formed particleboard comprising cross-bonded plies. Substitute for plywood in building.

Overhang

That portion of the roof structure that extends beyond the exterior walls of a building.