Cedar shake roof replacement, Washington

Why cedar roofs wear out in Washington

Cedar takes on water, and west of the Cascades it stays wet for months. Oregon State University Extension says moss on a wood roof holds moisture and debris against it, which invites fungi, speeds decomposition and shortens the roof's life; add shade from tall evergreens and the shakes split, cup, curl and rot, and need cleaning and re-treating to last. Aluminum absorbs nothing and cannot rot, and it does not rust in salt air on Puget Sound and the coast.

A cedar roof always comes off before an Interlock® roof goes on. That tear-off, and any deck repair the inspection finds under it, is in the written price from the start.

Keep the look: Shake and Cedar Shingle profiles

Interlock's Shake profile has deep, hand-split shadow lines; the Cedar Shingle profile has the flatter look of a sawn cedar roof, the look many Washington Craftsman, island and waterfront homes were built with. Both are aluminum, lock on all four sides with the fasteners concealed, and weigh roughly 0.4 to 0.7 lb per square foot depending on profile.

370 of the roofs in our job book in Washington are Shake or Cedar Shingle profiles.

If the house is in a historic district, check with your local historic landmarks commission before you choose; we bring samples and product documents for that review.

Fire and cedar

Class A Fire Rated Available, as a complete assembly: two layers of GAF VersaShield® over 15/32-inch plywood, per ASTM E108 / UL 790. The rating belongs to the assembly, not to the panel alone, and aluminum itself does not ignite. Untreated cedar shakes are commonly unrated, which matters east of the Cascades and anywhere a house backs onto forest. Our fire-resistant roofing guide covers it in detail.