Aggregate: A surfacing or ballast for a roof system. Aggregate can be rock, stone, crushed stone or slag, water-worn gravel, crushed lava rock or marble chips.



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

Edging Strips: boards nailed along eaves and rakes after cutting back existing wood shingles to provide secure edges for re-roofing with asphalt shingles.

Chimney Flashing: A corrosion-resistant sheet metal installed at the base of a chimney to prevent leaks.

Horizontal Siding: Provides style and functionality. Available in various materials, colors, textures and designs.

Vapor retarder: Any material used to prevent the passage of water vapor.

Underlayment: Asphalt saturated felt used beneath roofing to provide additional protection for the deck.

Hip: The external angle formed by the meeting of two sloping sides of a roof that have their wall plates running in different directions.

Exposed Nail Method: Application of role roofing in which all nails are driven into the cemented, overlapping course of roofing. Nails are exposed to the weather.

Gambrel roof: A type of roof containing two sloping planes of different pitch on each side of the ridge. The lower plane has a steeper slope than the upper. Contains a gable at each end.

Nesting: A method of re-roofing with new asphalt shingles over old shingles in which the top edge of the new shingle is butted against the bottom edge of the existing shingle tab.

Telegraphing: Shingle distortion that may arise when a new roof is applied over an uneven surface.

Starter Strip: Asphalt roofing applied at the eaves that provides protection by filling in the spaces under the cut out's and joints of the first course of shingles.

Drip Edge: A narrow strip of non-corrosive, non-staining, finishing material installed along the eaves and rakes to allow water run-off to drip clear of underlying construction. On eaves where gutters are present, this material is commonly called gutter apron.

Bitumen: Any of various flammable mixtures of hydrocarbons and other substances, occurring naturally or obtained by distillation from coal or petroleum, that are a component of asphalt and tar and are used for surfacing roads and for waterproofing.

Eaves: The lower border of a roof that overhangs the wall.

Steep Slope: Roof that pitches more than 45 degrees.

Cant Strip: A triangular-shaped strip of material used to ease the transition from a horizontal plane to a vertical plane. Cant strips can be made of wood, wood fiber, perlite, or other materials.

Ice dam: Condition formed at the lower roof edge by the thawing and re-freezing of melted snow on the overhang. Can force water up and under shingles, causing leaks.

Self-sealing Strip: Factory applied adhesive that bonds shingle courses together when exposed to the heat of the sun after application.

As with any service, understanding the basic vocabulary involved will help you avoid communication problems. This, of course, helps avoid mistakes where you end up getting a bigger repair than you really ever needed.