Wood Shake

A wood shake is a wooden roofing unit that has been split, rather than sawn, along the grain on at least one face. Splitting follows the natural fibres of the wood, so shakes have a rough, textured surface and straight, continuous grain, which makes them stronger and less likely to warp than sawn shingles. Shakes are thicker than shingles and produce a heavier, more rustic-looking roof.

Types

North American shakes are classified by how they are made:

• Handsplit and resawn: a split blank is run through a band saw diagonally, producing two shakes each with one split face and one sawn back.
• Tapersawn: sawn on both faces from a split block, giving a thick, tapered unit with a smoother surface than a handsplit shake.
• Straight-split and tapersplit: split on both faces; tapersplit shakes are tapered by reversing the block between each split.

The Cedar Shake & Shingle Bureau's product lines include Certi-Split (handsplit and split shakes) and Certi-Sawn (tapersawn shakes).

Sizes

North American shakes are most commonly 24 in (610 mm) long; 18 in (457 mm) shakes are sometimes called barn shakes, and 48 in (1.2 m) shakes are mainly used for siding.

Installation features

Because the rough split surfaces do not lie tightly together, shake roofs traditionally include a strip of roofing felt interlay between each course to stop wind-driven rain and snow being blown through the gaps; the Cedar Shake & Shingle Bureau's manual specifies felt interlay for shakes only. Shakes are fixed with corrosion-resistant fasteners and spaced slightly apart to allow for swelling.

Performance

Split shakes resist water penetration well along their grain, and their thickness gives them a longer service life than shingles of the same species, provided they can dry. They require more maintenance than many modern roofing materials: debris, moss and lichens must be removed, and shakes that are split or cupped need replacing. Like all wood roofs, untreated shakes are combustible, and pressure-impregnated fire-retardant shakes are required in many fire-prone jurisdictions.

Alternatives

Rubber, plastic and fibre-cement "shake-look" products imitate the appearance of wood shakes with lower maintenance, though they lack the natural texture and weathering of real wood.