Algae | Rooftop fungus that can leave dark stains on roofing. |
Angled Fasteners | Roofing nails and staples driven into decks at angles not parallel to the deck. |
APA | American Plywood Association. Tests and sets standards for all varieties of plywoods used in the U.S. |
Apron flashing | Metal flashing used at chimney fronts. |
ARMA | Asphalt Roofing Manufacturer’s Association. Organization of roofing manufacturers. |
Asphalt | 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. |
ASTM | The American Society for Testing and Materials. Organization that sets standards for a wide variety of materials, including roofing. |
Back-surfacing | Granular material added to shingle’s back to assist in keeping separate during delivery and storage. |
Blistering | Bubbles or pimples in roofing materials. Usually moisture related. In shingles blisters are either moisture under the material or moisture trapped inside the material. |
Blow-offs | When shingles are subjected to high winds, and are forced off a roof deck. |
Buckling | When a wrinkle or ripple affects shingles or their underlayments. |
Closed-cut valley | A shingle valley installation method where one roof plane’s shingles completely cover the other’s. The top layer is cut to match the valley lines. |
Cobra® | GAFMC’s respected brand name for ventilation products. |
Corrosion | When rust, rot or age negatively affect roofing metals. |
Counter-flashing | The metal or siding material that is installed over roof-top base flashing systems. |
Country Mansion® & Country Estates™ | GAFMC’s limited lifetime warranty shingle. |
Crickets | A peaked water diverter installed behind chimneys and other large roof projections. Effectively diverts water around projections. |
Cupping | When shingles are improperly installed over an existing roof or are over-exposed, they form a curl or cup. |
Deck | The substrate over which roofing is applied. Usually plywood, wood boards, or planks. |
Dormer | A raised roof extending out of a larger roof plane. |
Drip-edge | An installed lip that keeps shingles up off of the deck at edges, and extends shingles out over eaves and gutters, and prevents water from backing up under shingles. |
Dubl-Coverage® Mineral Guard | Roll roofing material with 19″ selvage edge for double coverage over roof deck. |
Eaves | The roof edge from the fascia to the structure’s outside wall. In general terms, the first three feet across a roof is termed the eave. |
End-laps | 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. (underlayments, rolled roofing) |
Exposure | The area on any roofing material that is left exposed to the elements. |
Gable roof | Traditional roof style; two peaked roof planes meeting at a ridge line of equal size. |
GAFCant® | GAFMC cant strips for deflecting water away from flashing areas. Typically used on low slope roofs. |
Golden Pledge® | GAFMC’s strongest limited warranty for shingles. America’s strongest steep slope warranty. |
Grand Sequoia® | GAFMC shingle with wood shake appearance. |
Grand Slate™ | GAFMC shingle with slate appearance. |
Granules | Crushed rock that is coated with a ceramic coating and fired, used as top surface on shingles. |
Ice Dam | When a snow load melts on a roof and re-freezes at the eave areas. Ice dams force water to “back-up” a roof and cause leakage. |
“L” flashing | Continuous metal flashing consisting of several feet of metal. Used at horizontal walls, bent to resemble an “L”. |
Laminated shingles | Shingles made from two separate pieces that are laminated together. GAFMC Timberline® Series, Country Mansion® and Grand Sequoia® Shingles. Also called dimensional shingles and architectural shingles. |
Laps | The area where roll roofing or rolled underlayments overlap one another during application (see also side laps and end laps). |
Low slopes | Roof pitches less than 4/12 are considered low sloped roofs. Special installation practices must be used on roofs sloped 2/12-4/12. |
Mansard | A roof design with a nearly vertical roof plane that ties into a roof plane of less slope at its peak. |
Mats | The general term for the base material of shingles and certain rolled products. |
Modified bitumen | Rolled roofing membrane with polymer modified asphalt and either polyester or fiberglass reinforcement. |
Mortar | Mixture of sand, mortar, limestone and water used in bonding a chimney’s bricks together. |
Nail-guide-line | Painted line on laminated shingles, to aid in the proper placement of fasteners. |
Nail-pop | When a nail is not fully driven, it sits up off the roof deck. |
Nesting | Installing a second layer of shingles aligning courses with the original roof to avoid shingle cupping. |
NRCA | The National Roofing Contractors Association. Respected national organization of roofing contractors. |
Open valley | Valley installation using metal down the valley center. |
Organic mat | Material made from recycled wood pulp and paper. |
Organic Shingles | Shingles made from organic (paper) mats. |
OSB | Oriented Strand Board. A decking made from wood chips and lamination glues. |
Over-driven | The term used for fasteners driven through roofing material with too much force, breaking the material. |
Over-exposed | Installing shingle courses higher than their intended exposure. |
Pitch | ratio of the rise of the roof to the span of the roof. |
Power vents | Electrically powered fans used to move air from attics and structures. |
Plastic cement | Asphalt based sealant. Also called bull, mastic, tar, asphalt cement. |
Plumbing vents | Term used to describe plumbing pipes that project through a roof plane. Also called vent stacks. |
Prevailing wind | The most common direction of wind for a particular region. |
Quarter sized | Term for the size of hand sealant dabs, size of a U.S. 25¢ piece. |
Racking | Method of installing shingles in a straight up the roof manner. |
Rake edge | The vertical edge of gable style roof planes. |
Release film | The plastic sheet installed on the back of Weather Watch® and StormGuard® underlayments. Used for packaging and handling. Remove before installation. |
Rigid vent | Hard plastic ridge vent material. |
Roof louvres | Rooftop rectangular shaped roof vents. Also called box vents, mushroom vents, airhawks, soldier vents. |
Roof plane | A roofing area defined by having four separate edges. One side of a gable, hip or mansard roof. |
Sawteeth | The exposed section of double thickness on Timberline® Series shingles. Shaped to imitate wood shake look on the roof. |
Self-sealant | Sealant installed on shingles. After installation, heat and sun will activate sealant to seal the shingles to each other. |
Selvage | The non exposed area on rolled roofing. Area without granules. Designed for nail placement and sealant. |
Shed roof | Roof design of a single roof plane. Area does not tie into any other roofs. |
Shingle-Mate® | GAFMC’s shingle underlayment. Breather type with fiberglass backing to reduce wrinkles and buckles. |
Side-laps | The area on rolled material where one roll overlaps the rolled material beneath it. Also called selvage edge on rolled roofing. |
Side-walls | Where a vertical roof plane meets a vertical wall. The sides of dormers etc. |
Soffit ventilation | Intake ventilation installed under the eaves, or at the roof edge. |
Smart Choice® Limited Warranty | GAFMC’s standard shingle limited warranty. |
Smart Choice® System Plus Limited Warranty | GAFMC’s next grade of enhanced warranty. Extended coverage for owners. |
Starter strip | The first course of roofing installed. Usually trimmed from main roof material. |
Steep slope roofing | Generally all slopes higher than 4/12 are considered steep slopes. |
Step-flashing | Metal flashing pieces installed at side-walls and chimneys for weather-proofing. |
StormGuard® | GAFMC waterproof underlayment. Film surfaced rolled underlayment, 1.5 squares coverage per roll. |
Tab | The bottom portion of traditional shingle separated by the shingle cut-outs. |
Tear-off | Removal of existing roofing materials down to the roof deck. |
Telegraphing | When shingles reflect the uneven surface beneath them. Shingles installed over buckled shingles may show some buckles. |
Timberline® Series | GAFMC’s trademark name for laminated wood shake style shingles. |
TIMBERTEX® | GAFMC enhanced Hip and Ridge Shingles. |
Transitions | When a roof plane ties into another roof plane that has a different pitch or slope. |
Under-driven | Term used to describe a fastener not fully driven flush to the shingles surface. |
Underlayments | Asphalt based rolled materials designed to be installed under main roofing material, to serve as added protection. |
Valleys | Area where two adjoining sloped roof planes intersect on a roof creating a “V” shaped depression. |
Vapor | Term used to describe moisture laden air. |
Ventilation | The term used in roofing for the passage of air from an enclosed space. |
Warm wall | The finished wall inside of a structure, used in roofing to determine how to install waterproof underlayments at eaves. |
Warranty | The written promise to the owner of roofing materials for material related problems. |
Waterproof underlayments | Modified bitumen based roofing underlayments. Designed to seal to wood decks and waterproof critical leak areas. |
Weather Stopper® Integrated Roofing System™ | GAFMC’s complete roofing system and components. |
Weather Watch® | GAFMC’s granule surfaced waterproof underlayment. |
Woven Valleys | The method of installing valleys by laying one shingle over the other up the valley center. |