ANSI: American National Standards Institute
Apron Flashing: A flashing located at the low end of a curb or penetration.
Architectural Shingle: Shingle that provides a dimensional appearance. See also Dimensional Shingle.
ASHI: American Society of Home Inspectors
Asphalt: A substance left as a residue after evaporating or otherwise processing crude oil or petroleum.
Blister: A pocket of air trapped between layers of felt or membrane. Blisters are usually caused by water or other foreign substances.
Blocking: Pieces of wood built into a roof assembly used to stiffen the deck around an opening, support a curb, or for use as a nailer for attachment of membranes or flashing.
Boot: A piece of material preformed to protect roof penetrations from dirt, moisture and other foreign and/or damaging substances.
Brake: A piece of equipment used for forming metal.
Brooming: Embedding a ply of roofing material into hot bitumen or adhesive by using a broom, squeegee, or other piece of equipment to eliminate voids and help ensure adhesion.
Bundle: An individual package of shingles or shakes.
Cap Flashing: A material used to cover the top edge of base flashings or other flashings. (See also Coping.)
Caulk: A material with no elastomeric properties used for sealing joints.
Closed-Cut Valley: A method of valley application in which shingles from one side of the valley extend across the valley while shingles from the other side are installed over the top of those and then trimmed back approximately 2 inches from the valley centerline.
Condensation: The conversion of water vapor to liquid state when warm air comes in contact with a cold surface.
Contact Cements: Adhesives used to adhere or bond roofing components.
Cupola: A relatively small roofed structure set on the ridge of a main roof area. Also known as a Crow’s Nest.
Curb: (1) 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, should be a minimum of eight inches (8") in height; (2) A raised roof perimeter that is relatively low in height.
Deck: The structural component of the roof of a building which provides the substrate to which the roofing system is applied.
Dimensional Shingle: A shingle that is textured, or laminated to produce a three-dimensional effect. Also known as Laminated and Architectural Shingles. Please be aware that there are also shingles being produced that can be classified as Dimensional but not as Laminated. These shingles are comprised of a single piece of material rather than two different materials laminated together.
Dormer: A framed projection through the sloping plane of a roof.
Downspout: A conduit for carrying water from a gutter, scupper, drop outlet or other drainage unit from roof to ground level.
Drip Edge: A steel flashing bent at a 90º angle that is placed along the outer perimeter of steep sloped buildings; used to help direct runoff water away from the building.
Dry Rot: Wood rot caused by certain fungi. Dry rot can result from condensation build-up, roof leaks that go untended, or from other problems. Dry rot will not remain localized. It can spread and damage any lumber touching the affected area.
Eave: A roof edge that extends out past the exterior wall line.
Exhaust Vent: A device used to vent air from the roof cavity with vents that are installed on or near the higher portions of the roof such as the ridge.
Exposure: The portion of the membrane that is not overlapped by the succeeding ply or course. Or, the portion of the roofing material exposed to the weather after being installed.
Fascia: Vertical roof trim located along the perimeter of a building, usually below the roof level. Its use can be either decorative or for waterproofing.
Fasteners: Devices used to secure roof system components.
Felt: A roofing sheet made of interwoven fibers. The fibers can be wood or vegetable for Organic Felts, glass fibers for fiberglass felts, polyester, or asbestos.
Flashing: Components used to seal the roof system at areas where the roof covering is interrupted or terminated. For example, pipes, curbs, walls, etc. all have special components that, when correctly installed, will help prevent moisture entry into the roof system or building.
Gable: A triangular-shaped portion of the endwall of a building directly under the sloping roof and above the Eave line.
Gable Roof: A roof configuration that has gable ends.
Gambrel: A roof that has two different pitches.
Granule: A small aggregate, naturally or synthetically colored, used to surface cap sheets, shingles, and other granule-surfaced roof coverings.
Gutter: A channel (usually sheet metal) installed along the downslope perimeter of a roof to convey runoff water from the roof to the drain leaders or downspouts.
Hip: The angle formed by the intersection of two sloping roof planes.
Hip Roof: A roof that rises by inclined planes on all sides of a building. The line where two adjacent sloping sides of a roof meet is called the Hip.
HVAC: Acronym for Heating, Ventilating, and Air Conditioning.
Ice Damn: Ice formed at the transition from a warm surface to a cold surface, such as along the overhang of a house. The build-up of ice is the result of ice or snow melting on the roof area over the warmer, living area of a building and then refreezing when it runs down and reaches the overhang.
Joist: Any of the parallel horizontal beams set from wall to wall to support the boards of a floor, ceiling or roof of a building.
Lap Cement: Asphalt-based roof cement used to adhere overlapping plies of asphalt roll roofing.
Masonry: Refers to bricks, concrete, or concrete blocks.
Material Safety Data Sheets (MSDS): Written descriptions of the chemicals in a product provided by the product’s manufacturer. MSDS also contain other information such as emergency procedures and safe handling.
Mopping: To apply hot asphalt or coat tar using a hand mop or mechanical applicator.
Nailer: A piece of lumber, preferably treated, that is secured to the deck, walls, or to premanufactured curbs. Nailers are used to receive fasteners for roof membranes. Generally, nailers are installed wherever it is necessary to secure base flashings and edge metal.
Ninety-Pound: Granule-surfaced or fiber glass or organic felt roll roofing that has a mass of approximately 90 pounds per 100 square feet
Open Valley: A valley where both sides of the roof are trimmed back from the centerline to expose the valley flashing material beneath.
Pitch: The angle made by the roof surface plane with the horizontal plane and expressed as the amount of vertical rise for every twelve inch (12") horizontal run. For instance, a roof that rises four inches (4") for every twelve inch (12") horizontal run, is expressed as having a "four in twelve" slope; often written as "4:12." Expressed as a percentage, the slope would be 33%, which is equal to 4 divided by 12.
Press Brake: A mechanical device used to form sheet metal into desired shapes and profiles.
Rake: The sloped perimeter edge of a roof that runs from the eaves to the ridge. The rake is usually perpendicular to the eaves and ridge.
Ridge: The line where two planes of roof intersect, forming the highest point on the roof that runs the entire length of the roof.
Ridge Cap: Material applied over the ridge or hip of a roof.
Roof Assembly: A term used to describe all of the roof components including structural roof deck.
Roofer: An individual who installs roof systems and materials.
Roof Jack: (1) A steel bracket fastened to the roof that is used to support toe boards. (2) A term used to describe a Pipe Boot or Flashing Collar.
Run: The horizontal dimension of a slope.
Shingle: (1) A single piece of prepared roofing material, either asphalt or wood, for use in steep slope roof systems. (2) To install a wood or asphalt shingle roof system.
Skylight: A transparent or translucent item that is designed to admit light and set over a curbed opening in the roof.
Slate: A fine-grained metamorphic rock that splits into thin, smooth-surfaced layers used in steep slope roofing applications.
Snow Guard: Devices secured to the roof to prevent snow and ice from sliding off of a roof.
Soffit: The underside of a roof overhang.
Soffit Vent: An intake ventilation device located in the soffit. An exhaust vent should be installed on or near the ridge of the roof to work in conjunction with the soffit vent in order to properly ventilate the attic space.
Soil Pipe: A pipe that penetrates a roof and is used to vent a building’s plumbing
Square: (1) 100 square feet of roof area (9.29 m2) in the USA. (2) 10 square meters (107.639 ft.2) of roof area using the metric system of weights and measures.
Starter Course: The primary course of roofing materials. The Starter course is installed along the downslope perimeter edge and usually covered by the first course of roofing.
Starter Strip: Strips of shingles (usually 3-Tab shingles with the tabs cut off) or roll roofing material that is laid along the eave line of the roof prior to the application of the first course of shingles. The starter strip is used to fill in the gaps created by shingle cutouts and joints.
Steep-Slope Roof: A roof with a slope exceeding 3 in 12 (25%). Deemed appropriate to receive water-shedding type roofing materials such as asphalt shingles, wood shakes and shingles, concrete or clay tile, etc.
Step Flashing: Pieces of metal or other material that are used to flash roof projections such as chimneys, walls, curbs, etc. The pieces are installed between each course of roofing and generally have a vertical flange equal in length to that of the horizontal flange.
Tab: The portion of an asphalt shingle that is outlined by the cutouts.
Tar (ASTM DEFINITION): A brown or black bituminous material, liquid or semi-solid in consistency, in which the predominating constituents are bitumens obtained as condensates in the processing of coal, petroleum, oil-shale, wood, or other organic materials.
Tear-Off: To remove a roof system down to the structural substrate.
Valley: The internal intersection of two sloping roof planes that runs from the eaves to the ridge. This intersection collects the most water run-off
Vent: An opening or device used to permit air or vapors to exit an enclosed structure.
Wind Uplift: (1) The upward displacement of a section of a roof system or component caused by movement of air from a location of higher air pressure, such as inside a building, to an area of lower air pressure, such as the surface of a roof during a windy day. Strong wind across the surface of a roof, especially at corners and along perimeters, creates low air pressure above the surface of the roof. Nature will automatically try to compensate for this by moving air from an area of higher pressure such as inside a building. If all penetrations and perimeters are not properly sealed, then "blow-off" can occur. (2) Displacement or blow-off of shingles or other roofing caused by the wind.