Three-Tab Shingle

A three-tab shingle is the basic form of asphalt strip shingle. Each piece is a single layer of asphalt-coated mat with two notches, called cutouts, along the lower edge. The cutouts divide the exposed part of the strip into three tabs that look like three separate shingles once installed, producing a flat, brick-like grid on the roof.

Dimensions and weight

The traditional North American ("English") size is about 12 in by 36 in (305 by 914 mm), laid with a 5 in (127 mm) weather exposure. Metric strip shingles, slightly larger at about 13 by 39 in (333 by 1000 mm), are laid with a 5-5/8 in (143 mm) exposure. Three-tab shingles typically weigh 190-250 lb per square, or roughly 9-12 kg/m².

Performance

Because the product is a single layer, it is thinner and lighter than laminated shingles and usually costs less. Inspection references note typical wind ratings of about 60-70 mph (97-113 km/h); in strong wind the individual tabs can lift and tear if the sealant strip has not bonded. Manufacturer warranties have commonly run 20-30 years, but typical real-world lives are commonly given as about 15-18 years, depending on climate and ventilation.

Use today

Three-tab shingles dominated the North American market for much of the 20th century. They are now losing share to architectural shingles, but remain common on lower-cost housing and rentals, and are still widely used as starter strips along the eaves and cut into pieces for hip and ridge caps. When a roof is repaired, colour and style matching can be difficult because product lines change over time.

Identification

An inspector can recognise a three-tab roof by the regular vertical slots repeating every 12 in (305 mm) and the even horizontal lines of each course. Laminated shingles, by contrast, have no cutouts and show irregular shadow lines.