Roofing Terminology


HomeOwner Tips

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.

Apron Flashing

Metal flashing used at chimney fronts.

Asphalt

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

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 caused by 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.

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. Effectively diverts water around projections.

Cupping

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.

Deck

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.

Dormer

A raised roof extending out of a larger roof plane.

Drip Edge

An installed lip that keeps shingles up off the deck at edges, and extends shingles out over eaves and gutters, and prevents

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.

Exposure

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

Fasteners

Nails or staples used to secure roofing to the deck.

Fiberglass Mat

Fibers condensed into strong, resilient mats for use in roofing materials.

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

Flashing Cement

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

Gable Roof

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

Granules

Crushed rock that is coated with a ceramic coating and fired, used as top surface on shingles.

Hand-Sealing

The method to assure sealing of shingles on very steep slopes, in high wind areas, and when installing 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 a peak and four separate hip legs.

Ice Dam

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.

“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. 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. Shingles can not be installed at slopes less than 2/12.

Mansard

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

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.

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.

Overdriven

The term used for fasteners driven through roofing material with too much force, breaking the material.

Overexposed

Installing shingle courses higher than their intended exposure.

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 WeatherWatch and StormGuard underlayments. Used for packaging and handling. Remove before installation.

Rigid Vent

Hard plastic ridge vent material.

Roof Louvers

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.

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.

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.

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.

Stepflashing

Metal flashing pieces installed at sidewalls and chimneys for weatherproofing.

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. Ex: Shingles installed over buckled shingles may show some buckles.

Transitions

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

Underdriven

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.

Warm Wall

The finished wall inside of a structure, used in roofing to determine how far up the deck 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.

Woven Valleys

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