What to Know About Roofing
Frequently Used Roofing Terms
Roof in need of repair.
Asphalt: A waterproofing agent used in various types of roofing materials. Also, asphalt plastic cement is used to seal and adhere roofing materials (also called mastic, blackjack, roof tar or bull).
Blistering: Bubbles or pimples in roofing materials, usually moisture related.
Blow-offs: When shingles are subjected to high winds and are forced off a roof deck.
Decking: The plywood, wood boards or planks which roofing is applied. (see also OSB and sheathing)
Drip Edge: An installed lip that keeps shingles up off of the deck at edges and extends shingles out over eaves and gutters to prevent water from backing up under shingles. (also see metal edge)
Downspouts: The drain or trough for a gutter to run into to move water away from the house.
Eaves: The roof edge from the fascia to the structure’s outside wall. The first three feet across a roof is termed the eave.
Flashing: Materials used to waterproof a roof around any projections through the roof deck.
Counter-flashing: The metal or siding material that is installed over roof-top based flashing systems.
Step flashing: Metal flashing pieces installed at side-walls and chimneys for weather-proofing.
Gable Roof: Traditional roof style; two peaked roof planes meeting at a ridge line of equal size.
Ice and Water Barrier: Self adhesive underlayment used in lower pitch areas and areas prone to ice damming and large concentrations of water.
Ice Damming: When snow melts and re-freezes at the eave areas. Ice dams force water to back-up and can cause leakage.
Laminated shingles: Shingles made from two separate pieces that are laminated together. Example: Timberline™
Mansard: A roof design with a nearly vertical roof plan that ties into a roof plane of less slope at its peak.
Metal Edge: An installed metal lip that keeps shingles up off of the deck at edges and extends shingles out over eaves and gutters to prevent water from backing up under shingles. (also see drip edge)
Mop Down: Modified roll roofing designed for flat roof applications, a better alternative to a 90-pound roll roofing application.
OSB: (Oriented Strand Board) A preferred application for decking made from wood chips and laminated glues.
Pitch: Ratio of the rise of the roof to the span of the roof.
Re-sheet: Installing new decking after all layers of shingles have been torn off. (sometimes referred to as a tear-off and re-sheet)
Ridge: A beginning or termination point at the top of the roof.
Sheathing: The plywood, wood boards or planks to which roofing is applied. (also see decking)
Soffit: The space between the eave and the overhang of the house. 3-Tab: A standard composition shingle that is 3 feet long with slits every 12 inches.
Timberline®: GAF Manufacturer’s Trademark name for laminated wood shake style shingles.
Tear-off: Removal of existing roofing materials down to the roof deck. Underlayment: A barrier material designed to be installed between the roofing shingles and the roof decking to serve as added protection. Brookside Roofing utilizes synthetic underlayment, a significantly thinner, lighter, and more efficient barrier.
Valley: Area where two adjoining sloped roof planes intersect on a roof creating a “V” shaped depression.