A

Algae

Roof top fungus that can leave stains on your roofing material

Algae Discoloration

A type of roof discoloration caused by algae; commonly called fungus growth

Aluminum

A non-rusting metal used in roofing for metal roofing and the fabrication gutters and flashings

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 used in the United States of America

Apron Flashing

Metal Flashing used at chimney fronts

Asphalt

A bituminous waterproofing agent used in various types of roofing materials

ASTM

The American Society of Testing and Materials - a voluntary organization that sets standards for a wide variety of materials, including roofing

B

Back-surfacing

Granular material added to shingles back to assist in keeping separate during delivery and storage

Ballast

A material installed over the top of a roof membrane to help hold it in place. Ballast are loose laid and can consist of aggregate, or concrete pavers

Base Ply

The primary apply of roofing material in a roof system

Base Sheet

An asphalt impregnated, or coated felt used as the first ply in some built-up and modified bitumen roof systems

Blistering

Bubbles in roofing materials. Usually moisture related. In shingles blisters are either moisture under the material or moisture trapped inside material

Blow-offs

When shingles are subjected to to high winds, and are forced off a roof deck

Buckling

When a wrinkle or ripple affects shingles or their underlayments

Built-up Roofs (BUR)

A flat or low-sloped roof consisting of multiple layers of asphalt and ply sheets

Bundle

A package of shingles - there are 3, 4, and 5 bundles per square

Butt Edge

The lower edge of the shingle tabs

C

Can't Strip

A triangular-shaped strip of material used to ease the transition from a horizontal plane to a vertical plane. Can't strips can be made of wood, wood fiber, perlite or other materials

Cap Sheet

A granule-surfaced membrane often used as the top ply of BUR or modified roof systems

Caulk

To fill a joint with mastic or asphalt cement to prevent leaks

Cement

See asphalt plastic cement

Caulk Line

A line made on the roof by snapping a taunt string or cord dusted with caulk. Used for alignment purposes

Class "A"

The highest-fire resistance rating for roofing as per ASTM E-108. Indicated roofing is able to withstand severe exposure to fire originating from sources outside the building

Class "B"

Fire-resistance rating that indicates roofing materials are able to withstand moderate exposure to fire originating from sources outside the building

Class "C"

Fire-resistance rating that indicates roofing materials are able to withstand light exposure to fire originating from sources outside the building

Closed-Cut-Valley

A shingle valley installation method where one roof plane's shingles completely cover the others. The top is cut to match the valley lines

Coating

A layer of viscous asphalt applied to the base material into which granules or other surfacing is embedded

Collar

Pre-formed flange placed over a vent pipe to seat the roof around the vent pipe opening - also called a vent sleeve

Cancelled Nail Method

Application of rolled roofing in which all nails are driven into the underlying course of roofing and covered by a cemented, overlapping course. Nails are not exposed to the weather

Condensation

The change of water to vapor to liquid when warm, moisture-laden air comes in contact with a cold surface

Coping

The piece of material used to cover the top of a wall and protect it from the elements. It can be constructed from metal, masonry or stone

Copper

A reddish-brown element that conducts heat and electricity very well. It is also used as a primary roof material as well as a flashing component. Cooper turns a greenish color after being exposed to the weather for a length of time

Corrosion

When rust, rot or age negatively affect roofing materials

Counter-Flashing

The metal or siding material that is installed over rooftop base flashing systems

Course

A row of shingles or roll roofing running the length of the roof

Coverage

Amount of weather protection provided by the roofing material. Depends on number of layers of material between the exposed surface of the roofing and the deck (i.e.. - single coverage, double cover, etc.)

Crickets

A peaked water diverter installed behind chimneys and other large roof projections. Effectively diverts water around projections

Cupola

A Relatively small roofed structure set on the ridge of a main roof area - also known as a crows nest

Cupping

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

Curb

A raised member used to support skylights, HVAC units, exhaust fans, hatches or other pieces of mechanical equipment above the level of the roof surface, and should be a minimum of eight inches in height

Cutout

The open portions of a strip shingle between the tabs

D

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

Double Coverage

Application of asphalt roofing such that the lapped portion is at least two inches wider than the exposed portion, resulting in two layers of roofing material over the deck

Downspout

A pipe for draining water from roof gutters - also called a leader

Drip Edge

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

Dry-In

The process of installing the underlayment in steep slope roofing, making a low-slope roof watertight

Dry Rot

Wood rot caused by certain fungi. Dry rot can result from condensation build-up, roof leaks that go unattended, or from other problems. Dry rot will not remain localized. It can spread and damage any lumber touching the affected area

E

Eaves

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

Eaves Flashing

Additional layer of roofing material applied at the eaves to help prevent damage from water backup.

Edging Strips

Boards nailed along Eaves and rakes after cutting back existing wood shingles to provide secure edges for re-roofing asphalt shingles

Elastomer

A material which after being stretched, will return to it's original shape

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.(i.E. - underlayments, rolled roofing)

Exposure

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

Exposure Nail Method

Application of roll roofing in which all nails are driven into the cemented, overlapping course of roofing.Nails are exposed to the weather

Exposure 1 Grade Plywood

Type of plywood approved by American Plywood Association for exterior use

F

Fascia

Vertical roof trim located along the perimeter of a building usually below the roof level

Fasteners

Nails or staples used in securing roofing to the deck. Felt-organic or paper-based rolled material saturated with asphalt to serve as roofing underlayment

Felt

Fibrous material saturated with asphalt and used as an underlayment or sheathing paper

FHA

The Federal Housing Authority - sets construction standards throughout the United States

Fiberglass Mat

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

Field

Refers to a central part of a roof away from the perimeter

Flange

Metal pan extending up and 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. Pieces of metal or roll roofing used to prevent seepage of water into a building around any intersection or projection in a roof such as vent pipes, chimneys, adjoining walls, dormer and valleys. Galvanize metal flashing should be a minimum 26-gauge

Flashing Cement

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

Free-Tab Shingles

Shingles that do not contain factory-applied strips or spots of self-sealing adhesive

G

Gable

The upper portion of a sidewall that comes to a triangular point at the ridge of slopping roof

Gable Roof

Traditional roof style - two-peaked roof planes meeting at a ridgeline of equal size

Galvalume

Trade name for a protective coating composed of aluminum zinc

Galvanize

To coat with zinc

Gambrel Roof

A type of roof containing two slopping planes of different pitch on each side of the ridge. The lower plane has a steeper slope than the upper and contains a gable at each end

Granules

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

Gutter

The trough that channels water from the eaves to the down spouts

H

Hand-sealing

The method to assure sealing of shingles on very steep slopes, in high wind areas, when installing in cold weather

Head Lap

Shortest distance from the butt edge of an overlapping shingle to the upper edge of a shingle in the second course below. The triple coverage portion of the top lap of strip shingles

Hex Shingles

Shingles that have the appearance of a hexagon after installation

High Nailing

When shingles are nailed or fastened above the manufactures specified nail location

Hip

The inclined external angle formed by the intersection of two slopping roof planes. Runs from the ridge to the eaves

Hip Legs

The down-slope ridges on the hip roofs

Hip Roof

A roof with four roof planes coming together at a peak and four separate hip legs

Hip Shingles

Shingles used to cover the incline external angle formed by the intersection of two slopping roof planes

I

Infrared Thermography

The use of an infrared camera to detect moisture in roof insulation

Insulation

Material used to help maintain a certain temperature in a building by reducing the flow of heat to and from that building

Interlocking Shingles

Individual shingles that mechanically fasten to each other to provide wind resistance

L