Roof discoloration resulting from a common algae, often mistaken as fungus growth.

The Asphalt Roofing Manufacturers Association, a trade association representing North American manufacturers of asphalt roofing materials.

A voluntary organization dedicated to the development of consensus standards, testing procedures, and specifications in various industries, including roofing.

Bituminous waterproofing material applied to roofing materials during manufacturing.

Thin liquid bitumen applied to a surface to enhance adhesion of self-adhering membranes and absorb dust.

Asphalt-based cement utilized to bond roofing materials, also known as flashing cement or mastic, conforming to ASTM D4586 (asbestos free).

Also referred to as Laminated Shingles, these are shingles containing multiple layers for added thickness.

Fine-mineral matter applied to the back side of shingles to prevent sticking together.

Part of flashing attached to or resting on the deck, directing water flow onto the roof covering.

Intended as the base or middle ply in residential self-adhering roll roofing systems.

Intended to be used as a base ply in self-adhering roll roofing systems.

Bubbles appearing on asphalt roofing after installation.

Reroofing with metric-size shingles method.

Flat or low-sloped roof with multiple layers of ply sheets embedded in hot asphalt.

Package containing shingles, typically 3, 4, or 5 bundles per square.

Lower edge of shingle tabs.

Mineral-surfaced material used alone or as top layer of multi-layer rolled roof covering system.

Filling a joint with mastic or asphalt cement to prevent leaks.

Refers to Asphalt Roof Cement.

Roof marking made by snapping a taut, chalk-dusted string for alignment.

Highest fire test classification for roofing, indicating resistance to severe external fire exposure.

Classification indicating moderate resistance to external fire exposure.

Classification indicating light resistance to external fire exposure.

Highest impact resistance classification per UL 2218 Impact test, indicating resistance to hailstorm impacts.

Valley treatment method where one side’s shingles extend across the valley, while the other side’s shingles are trimmed 2” from the valley centerline.

Pre-formed flange sealing the roof around a vent pipe opening, also known as vent sleeve.

Roll roofing application where nails are hidden, covered by cemented, overlapping courses.

Water vapor turning into liquid on contact with a cold surface.

Flashing attached vertically to prevent water from seeping behind the base flashing.

A row of shingles or roll roofing running along the roof’s length.

Number of layers between exposed roofing surface and deck.

Peaked saddle construction behind a chimney, preventing snow accumulation and deflecting water.

Open portions of a strip shingle between tabs.

Surface installed over framing members to which roofing is applied.

Framed window unit projecting through the sloping roof.

Asphalt roofing with overlapping portions at least 2” wider than exposed portion, forming two layers.

Pipe draining water from roof gutters, also known as leader.

Non-staining material along eaves and rakes, directing water run-off clear of underlying construction.

Roof’s horizontal lower edge.

Extra roofing layer at eaves to prevent water damage.

Roll roofing application where nails are exposed to weather.

Portion of roofing exposed to weather after installation.

Fibrous material saturated with asphalt, used as underlayment.

Core material in asphalt shingles made from glass fibers.

Metal pieces preventing water seepage around roof intersections and projections.

Upper triangular sidewall portion meeting at the ridge of a double sloping roof.

Simple two-sided roof above a gable.

Roof with two sloping planes of different pitch on each side, with a gable at each end.

Ceramic-coated crushed rock adding color and protection to asphalt roofing.

Trough channeling water from eaves to downspouts.

Shortest distance from butt edge of overlapping shingle to upper edge of shingle in second course below.

Shingles resembling hexagons after installation.

Inclined external angle formed where two sloping roof planes meet.

Roof with sloping planes on all four sides, no gables.

Shingles covering an inclined external angle formed by two sloping roof planes.

Formation at lower roof edge from thawing and refreezing of snow, forcing water under shingles.

Self-adhering underlayment at eaves to prevent water damage due to ice dams.

Shingles designed to withstand hail storm impacts.

Shingles mechanically fastening to provide wind resistance.

Shingles with multiple layers for extra thickness, also called three-dimensional shingles.

Covering one shingle or roll with another.

Asphalt-based cement adhering overlapping plies of roll roofing.

Installing shingles on roof slopes from 2” to less than 4” per foot.

Roof with two sloping planes on each side, the lower steeper than the upper, with gables at each end.

Inert materials added to asphalt in shingles for durability and resistance to fire and weathering.

Asphalt shingles and roll roofing covered with granules.

Re-roofing method with new shingles over old, where the new shingle’s top edge butts against the bottom edge of the existing shingle tab.

Shingles with single, solid tabs, no cutouts.

Wood-based panel without laminated veneer, like wafer board or oriented strand board.

Valley construction method where shingles on both sides are trimmed along chalk lines without extending across the valley.

Asphalt roofing base material made from cellulose fibers.

Roof portion extending beyond building’s exterior walls.

Wooden platforms for storing and shipping shingle bundles.

Roofing layer (e.g., one-ply, two-ply).

Accumulation of water on roof in low-lying areas.

Asphalt-based primer preparing surfaces for bonding with self-adhering asphalt sheets.

Vertically applying shingle courses up the roof.

Supporting framing member beneath the deck, sloping from ridge to wall plate.

Inclined roof edge over a wall.

Shingles with varying tab sizes and exposure.

Adding another layer of roofing over an existing one (maximum two layers allowed).

Plastic strip on self-sealing shingles preventing sticking in bundles.

Removing existing roof coverings and replacing with a new system.

Uppermost horizontal angle where two sloping roof planes meet.

Shingles covering the horizontal external angle formed by sloping roof planes.

Vertical distance from eaves line to ridge.

Asphalt roofing products in roll form.

Asphalt-saturated tape for flashing and patching asphalt roofing.

Horizontal distance from eaves to point under ridge, half the span.

Asphalt-impregnated felt used between deck and roofing material.

Styrene-Butadiene-Styrene, a synthetic polymer mixed with asphalt for flexibility.

Waterproofing underlayment protecting against water infiltration due to ice dams or wind-driven rain.

Shingles with factory-applied adhesive strips or spots.

Factory-applied adhesive bonding shingle courses when exposed to sunlight heat.

Roll roofing portion overlapped by succeeding course to achieve single or double coverage at the lap.

Slight differences in shingle color due to manufacturing.

Deck supporting roofing.

Roof with one sloping plane, no hips, ridges, valleys, or gables.

Roofing with one layer over the deck.

Roof incline expressed as the ratio of rise to run (e.g., 4/12 has 4in rise per 12in run).

Roll roofing with ground talc or mica, not granules-coated.

Finished underside of eaves.

Roof-penetrating vent pipe.

Horizontal distance from eave to eave.

Roof measure unit covering 100 square feet.

Shingles with tabs of the same size and exposure.

Installing asphalt shingles on slopes of 4” to 21” per foot.

Asphalt roofing at eave, providing extra protection under the first course of shingles.

Installing asphalt shingles on slopes greater than 21” per foot.

Base flashing method where a vertical surface meets a sloping roof plane.

Asphalt shingles with a single layer, three times long as wide.

Polypropylene underlayment alternative to felt.

Exposed portion of strip shingles between cutouts.

Mineral applied to back of shingles to prevent sticking.

Removing existing roofing system down to the structural deck.

Shingle distortion when new roof is applied over uneven surface.

See Laminated Shingles.

Roofing portion covered by succeeding course after installation.

Underwriters Laboratories, LLC.

Label indicating asphalt roofing’s fire and wind resistance level.

Asphalt-saturated felt or synthetic material under roofing for additional deck protection.

Internal angle formed by intersection of two sloping roof planes.

Material preventing water vapor passage.

Air outlet protruding through roof deck, like a pipe or stack.

See Collar.

Valley construction with woven shingles on both sides, no exposed valley flashing.