Architectural Shingle

An architectural shingle, also called a laminated or dimensional shingle, is an asphalt shingle built from two or more layers bonded together. The upper layer is cut into tabs or shapes of varying width, and the lower layer shows through the gaps. The result is a roof with irregular shadow lines that loosely imitates wood shakes or slate, rather than the flat grid of a three-tab roof.

Construction and size

Laminated shingles have no regular cutouts. Most are made in metric sizes of about 13 by 39 in (333 by 1000 mm). The extra layer makes them heavier: inspection references give about 240-320 lb per square (roughly 12-16 kg/m²), and high-end versions with up to five layers can approach 500 lb per square (about 24 kg/m²).

Performance

The double thickness generally gives better resistance to wind and more tolerance of minor deck irregularities. Typical wind ratings quoted for standard installation are around 70-110 mph (113-177 km/h), and about 110-130 mph (177-209 km/h) when the manufacturer's enhanced six-nail pattern is used. Manufacturer warranties commonly run from 30 years to "lifetime" terms, usually prorated and often limited to material. Typical service lives are commonly given as about 24-30 years, but heat, ventilation and installation quality strongly affect real performance.

Market position

In North America, architectural shingles have largely replaced three-tab shingles as the standard choice for new homes and re-roofing. Their irregular pattern also hides slight colour variation and deck unevenness better than flat strip shingles.

Installation notes

Architectural shingles need to be nailed in the manufacturer's specified nail zone, which is often a narrow band where the two layers overlap; nails placed too high may miss the lower layer and reduce wind resistance. Matching hip and ridge caps are usually sold separately because the laminated shingle cannot be folded over a ridge without cracking.