Re Roofing Over Architectural Shingles

Statistics by the national roof contractors association show that nine out of ten roofs in the us fail due to a ventilation issue.

Re roofing over architectural shingles.

Be sure to check with the shingle manufacturer regarding all warranty issues and installation requirements before re roofing. How to shingle over existing shingles and how to shingle a roof how to install roof shingles shingle layout lines h. Three tab shingles are a constant thickness while architectural shingles have multiple layers that create an uneven surface. The quick answer is yes you can re roof architectural shingles over existing architectural shingles however you must check with the shingle manufacturer as well.

The standard practice is to limit to a total of two layers of shingles. This article discusses how to prepare an existing asphalt shingle roof for a roof over or for re roofing with new asphalt shingles. If you look at the picture above you can see the difference. Beveled wood pieces called horsefeathers must be laid along the thick edges of the shakes to make a fairly flat surface.

All shingle manufacturers honor the warranty whether their products are used for a reroof or a new roof. Asphalt shingles can be laid over cedar shakes or shingles however this is a roofing project best left to pros. After that you should tear off old shingles before installing a new layer. If you re going strictly via code you can install a layer over a layer.

If the job is done correctly with the new layer of shingles laid flat over the existing shingles the old roof cushions the new one and serves as a secondary barrier should wind or water ever break through the new shingles. However we wouldn t recommend this practice. Local codes might not allow re roofing. Asphalt roof shingle re roofing advice.

Re roofing may affect the warranty on the new shingles. While both types are made up of the same essential components re roofing over architectural shingle is a different case altogether. Before you reshingle a roof read our step by step guide for adding new shingles over old ones. We also discuss proper asphalt shingle roof preparation for a roofover job.

Two layers is the maximum in most areas but some building codes allow only one.