Rooftop fungus that can leave dark stains on roofing.
Roofing nails and staples driven into decks at angles not parallel to the deck.
Metal flashing used at chimney fronts.
Asphalt Roofing Manufacturers Association. Organization of roofing manufacturers.
A bituminous waterproofing agent used in various types of roofing materials.
Asphalt Concrete Primer
Asphalt based primer used to prepare concrete and metal for asphalt sealant.
Asphalt Plastic Cement
Asphalt based sealant material, meeting ASTM D4586 Type I or II. Used to seal and
adhere roofing materials. Also called mastic, blackjack, roof tar, bull.
The American Society for Testing and Materials. Organization that sets standards
for a wide variety of materials, including roofing.
Granular material added to shingles back to assist in keeping separate during
delivery and storage.
Bubbles or pimples in roofing materials. Usually moisture related. In shingles blisters
are caused by either moisture under the material or moisture trapped inside the
When shingles are subjected to high winds, and are forced off a roof deck.
When a wrinkle or ripple affects shingles or their underlayments.
Closed Cut Valley
A shingle valley installation method where one roof planes shingles completely
cover the others. The top layer is cut to match the valley lines.
GAFs respected brand name for ventilation products.
The metal or siding material that is installed over roof-top base flashing systems.
GAFs limited lifetime warranty shingle.
A peaked water diverter installed behind chimneys and other large roof projections.
Effectively diverts water around projections.
When shingles are improperly installed over an existing roof or are over-exposed,
they may form a curl or cup. May also be due to a manufacturing defect.
The substrate over which roofing is applied. Usually plywood, wood boards, or planks.
Deck Armor™ - premium breathable roof deck protection. It provides a critical extra
layer of protection between your shingles and your roof deck — to help prevent wind-driven
rain (or water from other sources) from infiltrating under your shingles and causing
damage to your roof structure or to the inside of your home.
A raised roof extending out of a larger roof plane.
An installed lip that keeps shingles up off the deck at edges, and extends shingles
out over eaves and gutters, and prevents
Dubl-Coverage Mineral Guard®
Roll roofing material with 19" selvage edge for double coverage over roof deck.
The roof edge from the fascia to the structures outside wall. In general terms,
the first three feet across a roof is termed the eave.
When installing rolled products in roofing, the area where a roll ends on a roof,
and is overlapped by the next section of rolled material. EWA
Engineered Wood Association. Tests and sets standards for all varieties of plywood
used in the U.S.
The area on any roofing material that is left exposed to the elements.
Nails or staples used to secure roofing to the deck.
The Federal Housing Authority sets construction standards throughout the U.S.
Fibers condensed into strong, resilient mats for use in roofing materials.
Metal pan extending up or down a roof slope around flashing pieces. Usually at chimneys
and plumbing vents
Materials used to waterproof a roof around any projections
Sealant designed for use around flashing areas, typically thicker than plastic cement.
Traditional roof style; two peaked roof planes meeting at a ridge line of equal
GAF cant strips for deflecting water away from flashing areas. Typically used
on low slope roofs.
GAFs strongest limited warranty for shingles. Americas strongest steep
GAF shingle with wood shake appearance.
GAF shingle with slate appearance.
Crushed rock that is coated with a ceramic coating and fired, used as top surface
The method to assure sealing of shingles on very steep slopes, in high wind areas,
and when installing in cold weather.
When shingles are nailed or fastened above the manufacturers specified nail
The down-slope ridges on hip roofs.
A roof with four roof planes coming together at a peak and four separate hip legs.
When a snow load melts on a roof and re-freezes at the eave areas. Ice dams force
water to "back-up" under shingles and cause leakage.
Continuous metal flashing consisting of several feet of metal. Used at horizontal
walls, bent to resemble an "L".
Shingles made from two separate pieces that are laminated together such as GAF
Timberline® Series, Country Mansion® and Grand Sequoia®
Shingles. Also called dimensional shingles and architectural shingles.
The area where roll roofing or rolled underlayments overlap one another during application
(see also side laps and end laps). Liberty™
Self-adhering low-slope roofing. Liberty™ systems are applied without torches, open
flames, hot asphalt, or messy solvent-based adhesives.
Roof pitches less than 4:12 are considered low sloped roofs. Special installation
practices must be used on roofs sloped 2:12-4:12. Shingles can not be installed
at slopes less than 2/12.
A roof design with a nearly vertical roof plane that ties into a roof plane of less
slope at its peak.
The general term for the base material of shingles and certain rolled products.
Rolled roofing membrane with polymer modified asphalt and either polyester or fiberglass
Mixture of sand, mortar, limestone and water used in bonding a chimneys bricks
Nail Guide Line
Painted line on laminated shingles, to aid in the proper placement of fasteners.
When a nail is not fully driven, it sits up off the roof deck.
Installing a second layer of shingles aligning courses with the original roof to
avoid shingle cupping.
The National Roofing Contractors Association. Respected national organization of
Valley installation using metal down the valley center.
Material made from recycled wood pulp and paper.
Shingles made from organic (paper) mats.
Oriented Strand Board. A decking made from wood chips and lamination glues.
The term used for fasteners driven through roofing material with too much force,
breaking the material.
Installing shingle courses higher than their intended exposure.
Term for the size of hand sealant dabs, size of a U.S. 25¢ piece.
Method of installing shingles in a straight up the roof manner.
The vertical edge of gable style roof planes.
The plastic sheet installed on the back of WeatherWatch® and StormGuard®
underlayments. Used for packaging and handling. Remove before installation.
Hard plastic ridge vent material.
Rooftop rectangular shaped roof vents. Also called box vents, mushroom vents, airhawks,
A roofing area defined by having four separate edges. One side of a gable, hip or
The exposed section of double thickness on Timberline® Series shingles
- also called dragon teeth. Shaped to imitate wood shake look on the roof.
Sealant installed on shingles. After installation, heat and sun will activate sealant
to seal the shingles to each other.
The non exposed area on rolled roofing. Area without granules. Designed for nail
placement and sealant.
Roof design of a single roof plane. Area does not tie into any other roofs.
GAFs shingle underlayment. Breather type with fiberglass backing to reduce
wrinkles and buckles.
The area on rolled material where one roll overlaps the rolled material beneath
it. Also called selvage edge on rolled roofing.
Where a vertical roof plane meets a vertical wall. The sides of dormers etc.
Intake ventilation installed under the eaves, or at the roof edge.
GAF Shingle & Accessory Ltd. Warranty
GAFs standard shingle limited warranty.
The first course of roofing installed. Usually trimmed from main roof material.
Generally all slopes higher than 4/12 are considered steep slopes.
Metal flashing pieces installed at sidewalls and chimneys for weatherproofing.
GAF waterproof underlayment. Film-surfaced rolled underlayment, 1.5 squares coverage
The bottom portion of traditional shingle separated by the shingle cut-outs.
Removal of existing roofing materials down to the roof deck.
When shingles reflect the uneven surface beneath them. Ex: Shingles installed over
buckled shingles may show some buckles.
GAFs trademark name for laminated wood-shake-style shingles.
GAF enhanced Hip and Ridge Shingles.
When a roof plane ties into another roof plane that has a different pitch or slope.
Term used to describe a fastener not fully driven flush to the shingles surface.
Asphalt-based rolled materials designed to be installed under main roofing material
to serve as added protection.
Area where two adjoining sloped roof planes intersect on a roof creating a "V"
Term used to describe moisture laden air.
The finished wall inside of a structure, used in roofing to determine how far up
the deck to install waterproof underlayments at eaves.
The written promise to the owner of roofing materials for material related problems.
Modified bitumen based roofing underlayments. Designed to seal to wood decks and
waterproof critical leak areas.