Although they are rapidly disappearing in San Diego, occasionally we see old wood shake shingle roof systems.
Over 25 years ago wood shingle roof systems were very common in San Diego and were known at the time to be an upgraded type of roof system. But over time they have been found to be highly flammable and do not perform very well. With new local fire codes, we will no longer find these roofs in existence in the next few years. In San Diego any new construction, repairs, replacements, and alterations must be able to withstand severe exposure to fire. If a home with a wood shake shingle roof needs any roof repairs, they will need to do a roof tear-off and get a new roof.
Given the susceptibility of our area to wildfires, you definitely want your home protected by a Class A fire-rated roof. If you like the look of wood shake shingles, you can replace them with cement roofing tiles designed to look like wood shake.
Wood Shake Shingle Tear-Off or Roof Removal
When replacing an old Wood Shake Shingle Roof, the first step is to do a roof tear off down to the skip sheathing. Skip sheathing is a roofing surface that consists of 1”x4” or 1”x5” boards that are installed perpendicular to the rafters and provide a couple inches of spacing between each row of boards. Back in the day when these wood shingle roofs were installed the ideal way to install the wood shingle was over skip sheeting instead of plywood or plankboard because the premise was that the wood can breath easier with the wood slat spacing and therefore last longer. But, we have found through time and experience that really isn’t the case.
We now know that wood shake roofs actually last longer when installed on a flat plywood roof surface. When these are torn off, full sheeting, either plywood or known in today’s industry as OSB board is installed on top of the skip sheeting as a wood base onto which we apply the new roofing material.
This particular roof not only had wood shake shingles installed but it also had a layer of asphalt shingles installed on top of the existing wood shake shingles. Once both layers had been removed, we installed 4’x8’ OSB sheathing on top of the skip sheathing. OSB stands for “oriented strand board,” which consists of compressed wood strands bonded together by resin. These boards are much stronger and stiffer than traditional plywood boards.
With the proper full sheeting in place, we were able to continue with the rest of the roofing process. This included installing proper underlayment for an asphalt shingle roof, installing Owens Corning asphalt shingle on the entire roof, installing an Owens Corning ridge vent, reinstalling a solar tube, and installing all necessary flashings. The new roof will last for years and years and looks much better than the existing roof.
You can see the entire process on this home in San Diego.