Glossary of Common ConstructionTerms


CONDENSATION - The appearance of moisture (water vapor) on the surface of an object caused by warm moist air coming into contact with a colder object which can occur without proper roof ventilation. This can result in mold growth or sheathing rot.

DORMER - The house-like structure which projects from a sloping roof.

DRIP EDGE - A device designed to prevent water from running back or under an overhang. (Other names: metal edging, aluminum trim)

FASCIA - Any cover board or framed metal assembly at the edge or eaves of a flat, sloping, or overhanging roof which is placed in a vertical position to protect the edge of the roof assembly,(generally behind a gutter).

FELT - A very general term used to describe composition of roofing ply sheets, consisting of a mat of organic or inorganic fibers unsaturated, impregnated with asphalt or coal tar pitch, or impregnated and coated with asphalt.

FLASHING, COUNTER - The formed metal secured to a wall, curb, or roof top unit to cover and protect the upper edge of a base flashing and its associated fasteners.

FLASHING, STEP - Individual small pieces of metal flashing material used to flash around chimneys, dormers, and such projections along the slope of a roof. The individual pieces are overlapped and stepped up the vertical surface.

MANSARD ROOF - A roof which rises by inclined planes from all four sides of a building. The sloping roofs on all four sides have two pitches, the lower pitch usually very steep and the upper pitch less steep.

RAKE - The angle of slope of a roof rafter, or the inclined portion of a cornice (Follow gutter line to the end, then the board from there to the peak, that's the rake boards/edge)

SHEATHING - Plywood, gypsum, or wood fiber encasing walls, ceilings, floors and roofs of framed buildings.

VENT PIPE - A vertical pipe of relatively small dimensions which protrudes through a roof to provide for the ventilation of gasses.

VENTING - The process of installing roof vents in a roof assembly to relieve vapor. (Example: Ridge vents, roof vents, soffitt vents, power fan)