Asphalt: A waterproofing agent applied to other roofing materials during the manufacturer process.
Balanced system: A ventilation system where 50% of the required ventilating area is provided by vents located in the upper portion of the roof with the balance provided by undereave or soffit vents.
Base flashing: Used to direct water onto the roof covering, base flashing is part of the roof that’s attached to the deck.
Blisters: Various sized bubbles that can form within an asphalt roof, often after installation.
Built-up roof: Low-slope or flat roof which consists of asphalt & ply sheets in multiple layers.
Bundle: A collection of shingles. 3, 4 or 5 bundles are usually included within a square.
Butt edge: The lower edge of shingle tabs
Caulk: Used to fill any joints and prevent potential leaks.
Chalk line: A line made on the roof by snapping a taut string or cord dusted with chalk. Used for alignment purposes.
Closed cut valley: A method of valley treatment in which shingles from one side of the valley extend across the valley, while shingles from the other side are trimmed two inches from the valley centerline. The valley flashing is not exposed.
Collar: Also called a vent sleeve, a collar is used to seal the roof around the vent pipe opening.
Concealed nail method: Application of roll roofing in which all nails are driven into the underlying course of roofing and covered by a cemented, overlapping course. Nails are not exposed to the weather.
Condensation: Water that collects droplets when humid air comes in contact with a cold surface.
Counter flashing: The part of flashing that’s attached to a vertical surface to help stop any water from making its way behind the base flashing.
Course: A row of shingles or roll roofing running the length of the roof.
Cricket: A peaked saddle construction at the back of a chimney to help prevent accumulation of snow and ice and to deflect water around the chimney.
Deck: The surface installed over the supporting framing members to which the roofing is applied.
Dormer: A framed window unit projecting through the sloping plane of a roof.
Downspout: A pipe for draining water from roof gutters. Also called a leader.
Drip edge: A noncorrosive, nonstaining material used along the eaves and rakes to allow water runoff to drip clear of underlying construction.
Eaves: The horizontal, lowest edge of a sloped roof that extends beyond the exterior wall.
Felt: Fibrous material saturated with asphalt and used as an underlayment or sheathing paper.
Flashing: Pieces of metal or roll roofing used to prevent seepage of water into a building around any intersection or projection in a roof such as vent pipes, chimneys, adjoining walls, dormers and valleys.
Gable: The upper portion of a sidewall that comes to a triangular point at the ridge of a sloping roof.
Gable roof: A type of roof containing a sloping plane on each side of a single ridge with a gable at each end.
Gambrel roof: A type of roof containing two sloping planes of different pitch on each side of the ridge. The lower plane has a steeper slope than the upper. Features a gable at each end.
Granules: Ceramic-coated colored crushed rock that is applied to the exposed surface of asphalt roofing products.
Gutter: The trough that channels water from the eaves to the downspouts.
Hip: The inclined external angle formed by the intersection of two sloping roof planes. Runs from the ridge to the eaves.
Hip roof: A type of roof containing sloping planes of the same pitch on each of four sides. Contains no gables.
Hip shingles: Shingles used to cover the inclined external angle formed by the intersection of two sloping roof planes.
Ice dam: Condition formed at the lower roof edge by the thawing and refreezing of melted snow on the overhang. Can force water up and under shingles, causing leaks.
Lap: To cover the surface of one shingle or roll with another.
Low slope application: Method of installing asphalt shingles on roof slopes between two and four inches per foot.
Louver: A slanted opening for ventilation.
Mansard roof: A type of roof containing two sloping planes of different pitch on each of four sides. The lower plane has a much steeper pitch than the upper, often approaching vertical. Includes no gables.
Mineral stabilizers: Finely ground limestone, slate, traprock or other inert materials added to asphalt coatings for durability and increased resistance to fire and weathering.
Natural ventilation: A ventilation system utilizing ventilators installed in openings in the attic and properly positioned to take advantage of natural air flow to draw hot summer or moist winter air out and replace it with fresh outside air.
Normal-slope application: Method of installing asphalt shingles on roof slopes between 4 inches and 21 inches per foot.
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.
Overhang: That portion of the roof structure that extends beyond the exterior walls of a building.
Pallets: Wooden platforms used for storing and shipping bundles of shingles.
Pitch: The degree of roof incline expressed as the ratio of the rise, in feet, to the span, in feet.
Ply: The number of layers of roofing (e.g. one-ply, two-ply).
Rafter: The supporting framing member immediately beneath the deck, sloping from the ridge to the wall plate.
Rake: The inclined edge of a sloped roof over a wall from the eave to the ridge.
Ridge: The uppermost, horizontal external angle formed by the intersection of two sloping roof planes.
Ridge shingles: Shingles used to cover the horizontal external angle formed by the intersection of two sloping roof planes.
Rise: The vertical distance from the eaves line to the ridge.
Roll roofing: Asphalt roofing products manufactured in roll form.
Roofing cement: A compound used to seal flashings, seal down shingles and for other small waterproofing jobs. Where cement is required for sealing down shingles, use a dab about the size of a quarter unless otherwise specified.
Run: The horizontal distance from the eaves to a point directly under the ridge. One half the span.
Self-sealing shingles: Shingles containing factory-applied strips or spots of self-sealing adhesive.
Shading: Slight differences in shingle color that may occur as a result of normal manufacturing operations.
Sheathing: Exterior-grade boards used as a roof deck material.
Shed roof: A roof containing only one sloping plane. Has no hips, ridges, valleys or gables.
Slope: The degree of roof incline expressed as the ratio of the rise, in inches, to the run, in feet.
Soffit: The finished underside of the eaves.
Soil stack: A vent pipe that penetrates the roof.
Span: The horizontal distance from eaves to eaves.
Square: A unit of roof measure covering 100 square feet.
Starter strip: Asphalt roofing applied at the eaves that provides protection by filling in the spaces under the cutouts and joints of the first course of shingles.
Steep-slope application (Mansard): Method of installing asphalt shingles on roof slopes greater than 21 inches per foot.
Step flashing: Flashing application method used where a vertical surface meets a sloping roof plane.
Strip shingles: A single-layer shingle commonly known as a three-tab shingle because it has three tabs.
Tab: The exposed portion of strip shingles defined by cutouts.
Three-tab shingle: A single-layer shingle having three tabs.
Undereave: Underside area of the overhang at the eave of the roof.
Underlayment: A layer of asphalt-saturated felt (sometimes referred to as tar paper) which is laid down on a bare deck before shingles are installed to provide additional protection for the deck.
Valley: The internal angle formed by the intersection of two sloping roof planes to provide water runoff.
Vent: Any outlet for air that protrudes through the roof deck, such as a pipe or stack. Any device installed on the roof, gable or soffit for the purpose of ventilating the underside of the roof deck.
Ventilators: Devices that eject stale air and circulate fresh air (e.g. ridge, roof, gable, undereave, foundation or rafter vents and vented soffit panels).
Woven valley: Method of valley construction in which shingles from both sides of the valley extend across the valley and are woven together by overlapping alternate courses as they are applied. The valley flashing is not exposed.