Glossary

Below is a list of commonly used words in the roofing industry.
A
Acrylic Coating – A coating system with an acrylic resin base.

Adhere – The clinging of one surface to another.

Aggregate – A surfacing or ballast for a roof system in the form of a rock or stone.

Algae – Rooftop fungus that can leave dark stains on roofing.

Aluminized Steel – Sheet steel with a thin aluminum coating on the surface to enhance the steels ability to withstand weathering.

Ambient Temperature – The temperature of the air.

ANSI – American National Standards Institute.

Angled Fasteners – Roofing nails and staples driven into decks at angles not parallel to the deck.

Apron Flashing – Metal flashing used at chimney fonts.

Asbestos – Used for fire proofing and sometimes used for the reinforcement of roofing materials.

Asphalt – A bituminous waterproofing agent used in various types of roofing materials.

Asphalt Primer – Asphalt based primer used to prepare concrete and metal for asphalt sealant.

Asphalt Cement – Asphalt bases sealant material, meeting ASTM D4586 Type I or II. Used to seal and adhere roofing materials. Also called roof tar, mastic.

ASTM – The American Society for Testing and Materials. Organization that sets the standards for a wide variety of materials, including roofing.

B
Back-surfacing – Granular material added to shingle’s back to assist in keeping separate during delivery and storage.

Base Flashing – Roof membrane material used to seal a roof at the vertical plane intersections, such as a roof to wall, or roof-curbs.

Base Sheet – Asphalt or coated felt used as the first ply in some built-up and modified bitumen roof systems.

Bird Bath – Small amounts of water on a roof that quickly evaporates.

Bitumen – A component of asphalt and tar that are used for waterproofing.

Blistering – Bubbles in roofing materials. Usually moisture related, in shingles, moisture is under the material or trapped inside.

Blow-offs – When shingles are subjected to high winds, and are forced off a roof deck.

Bond – The force holding two components in positive contact.

Bonding Agent – A chemical used to create a bond between two layers.

Boot – A piece of material pre-formed to protect roof penetrations from dirt, moisture and other damaging materials.

Buckling – When shingles or their underlayments have a wrinkled or ripple effect.

C
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 – Type of 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.

Crickets – A peaked water diverter installed behind chimneys and other large roof projections. It effectively diverts water around projections.

Cupping – When shingles are improperly installed over an existing roof or over exposed, they form a curl or cup.

D
Deck – The substrate over which roofing is applied. Usually plywood 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.

E
Eaves – The roof edge from the fascia to the structure’s outside wall. Mostly, 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. Usually, underlayments or other rolled roofing products.

Exposure – The area on any roofing material that is left exposed to the elements.

F
Fasteners – Nails or staples used in securing roofing to the deck.

Flange – Metal pan extending up or down a roof slope around flashing pieces. Usually at chimneys and plumbing vents.

Flashing – Materials used to waterproof a roof around any projections through the roof deck.

Flashing Cement – Sealant designed for use around flashing areas, typically thicker than plastic cement.

G
Gable – Traditional roof style; two peaked roof planes meeting at a ridge line of equal size.

Golden Pledge – GAF ELK’s strongest limited warranty for shingles.

Granules – Crushed rock that is coated with a ceramic coating and fired, the top surface of shingles.

H
Hand-Sealing – The method to assure sealing of shingles on very steep slopes, in high wind areas, or when installing shingles in cold weather.

High Nailing – When shingles are nailed or fastened above the manufacturer’s specified nail location.

Hip Legs – The down-slope ridges on hip roofs

Hip Roof – A roof with four roof planes coming together at the peak with four separate hip legs.

I
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
“L” Flashing – Continuous metal flashing consisting of several feet of metal. Used on horizontal walls, bent to resemble an “L”.

Laminated Shingles – Shingles made from two separate pieces that are laminated together. Also called dimensional or architectural shingles.

Low Slope – Roof pitches less than 4/12 are considered low sloped roofs.

M
Mansard – A roof design with a nearly vertical roof plane that ties into a roof plane of less slope at its peak.

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 chimneys bricks together.

N
Nail-Guideline – 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.

O
Open Valley – Valley installation using metal down the center of the valley.

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.

P
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 mastic, tar, asphalt cement.

Plumbing Vents – The 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.

Q
Quarter sized – Term for the size of hand sealant dabs.

R
Racking – Method of installing shingles in a straight up the roof manner.

Rake Edge – The vertical edge of gable style roof planes.

Ridge Vent – Hard plastic ridge vent material.

Roof Louvers – Rooftop rectangular shaped roof vents. Also called box vents, mushroom vents.

Roof Plane – A roofing area defined by having four separate edges. One side of a gable, hip or mansard roof.

S
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 – GAF ELK’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.

Soffit Ventilation – Intake ventilation installed under the eaves, or at the roof edge.

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 slope.

Step-Flashing – Metal flashing pieces installed at side-walls and chimneys for weather-proofing.

StormGuard – GAF ELK’s waterproof underlayment. Film surfaced rolled underlayment.

T
Tab – The bottom portion of traditional shingle separated by the shingle cut-outs.

Tear-Off – Removal of existing roofing material down to the roof deck.

Telegraphing – When shingles reflect the uneven surface beneath them. Shingles installed over buckled shingles may show telegraphing.

TimberTex – GAF ELK’s enhanced Hip and Ridge Shingles.

Transitions – When a roof plane ties into another roof plane that has a different pitch or slope.

U
Under-Driven – The term used to describe a fastener not fully driven flush to the shingle surface.

Underlayments – Asphalt based rolled materials designed to be installed under main roofing material, serve as added protection.

V
Valleys – Area where two adjoining sloped roof planes intersect on a roof creating a “V” shaped depression.

Vapor – Term used to describe moisture.

Ventilation- The term used in roofing for the passage of air from an enclosed space.

W
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 Watch – GAF ELK’s granule surfaced waterproof underlayment.

Woven Valleys – The method of installing valleys by laying one shingle over the other up the valley center.