I have had hundreds of owners in the area have problems with their shake roofs. i finally got fed up and sent this letter to a local HOA . opinions please.
Due to the overwhelming amount of questions and problems arising from home owners with installations of Cedar Shakes on their roof, we at Enhanced Roofing and Remodeling have come to the conclusion that improper decking material being used is the main factor in the majority of problems we have found in the Northern Virginia. Though climate and inadequate ventilation are factors they do not appear to be the main reason Cedar Shakes in the area fail, some appear to last longer on different homes through out the area though very few last longer than 17-20 years. Asphalt shingles which have a 25 year manufactures warranty tend to last the complete 25 years. Roughly 85% of all Cedar shakes installed on roofs in area rarely last more than 10, makes you wonder why a material that cost approximately $350.00 per square “10x10 area” versus 45.00 per square does notlast anywhere near as long as shingles.
Cedar Shake roofs should be installed over 1x4 decking 3 1/2 " apart allowing the Cedar shakes to breathe, NOT plywood of any sort. I have included a sample of the decking and what it should look like taken right off a bundle of cedar shakes.
I have also contacted the manufacture and discussed the issues with them personally, they basically say we do not tell Builders how to build their homes, but they by far recommend split decking over plywood decking in any region. But I can insure after being in the business for almost 25 years that if they were called into inspect a roof for warranty issues they would not cover the warranty they provide if the roof is installed on solid decking, they also say any shakes in the Northern Va. area must be Pressure Treated for any warranty to exist.
Sound bout right too you guys?