between cedar shingles and shakes

Tt"r DTFFERE\cE between cedar |- shakes and shingles is less clear now than it was -50 y"u., ugo. Initially, cedar shingles were sawn from a block, while cedar shakes were split off using a mallet and froe.

Cedar shingles are more precisely milled than shakes, and provide a more refined classic appearance, which is well suited to a wide range of styles. Shingles were the siding of choice for the post-Victorian "shingle style" of the late l9th century, as well as for the many styles of the Arts and Crafts period. Cedar shingles were very prevalent in the hundreds of Craftsman-style bungalows designed by Gustav Stickley, and were frequently specified for both roofing and siding installations.

Cedar shake installations provide a more irregular, rustic appearance. They make a less sophisticated, more charming statement that works well for some smaller cottage styles.

Most cedar shakes today are made by machines, and are sawn on at least one side. Shakes are sometimes machine-grooved to appear more like authentic hand-split shakes. Although cedar shakes today are seldom hand split, they still follow the dimensional rules of their predecessors, which vary by grade.

Shakes are thicker than shingles, ranging from 112" to 3l4" or greater at the butt end, while shingles range from about 318' to 112'

Functionally, the most important difference between cedar shakes and shingles is that shingles are milled more precisely than shakes. Cedar shakes are more irregular and don't lay as flat when installed. This creates gaps that can be penetrated by wind blown precipitation.

Because shakes can be penetrated by wind-blown rain or snow, a layer of felt paper is required between courses for roofing installations. Interleaving felt paper helps blocks wind-blown precipitation, and also allows shakes to be installed with two layers of shakes and one layer of felt paper-rather than three layers of shakes, which would be quite thick.

Unfortunately, when installing cedar shakes, many roofers take advantage of this felt interlayer as a license to ignore the code requirements. Joints between cedar shakes must still be offset by at least 1-ll2" ffom course to course.

When joints in adjacent courses are aligned, or nearly so, the only protection from the elements is the felt paper, which has already been riddled with nail holes, and is easily torn. The felt underlayment was designed for temporary protection and as a secondary barrier for sparse and intermittent.leaks, not as a primary weather oarTler.

Cedar shingle installations are more precise, lay flat, and are never installed with felt interleavins. For roofing. shingles are always initalled so there are three layers of shingles at any point. Cedar shingles, properly installed as three overlapping layers, provide a highly weatherproof system, even in extreme weather.

- Bryan Kirkey is president of Ecoshel Inc., Atlanta, Ga., manufacturer of a patented cedar shingle system for siding and roofing. Reach him via www.ecoshel.com.