Re Roofing Over Dimensional Shingles

Re roofers have tricks to lay new roof shingles over old so that the same step ups between courses are maintained but if any old shingles are cupped curled or otherwise misshapen those defects will telegraph through to the new layer.

Re roofing over dimensional shingles.

Before you reshingle a roof read our step by step guide for adding new shingles over old ones. That brings their weight in at around 100 lbs per shingle. Asphalt roof shingle re roofing advice. All shingle manufacturers honor the warranty whether their products are used for a reroof or a new roof.

This article discusses how to prepare an existing asphalt shingle roof for a roof over or for re roofing with new asphalt shingles. 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. Most people would limit this practice to a total of two layers of shingles. This article series discusses best practices in the selection and installation of residential roofing.

These shingles are reasonably heavy and can weight twice as much as regular asphalt shingles or sometimes even more. Beveled wood pieces called horsefeathers must be laid along the thick edges of the shakes to make a fairly flat surface. The standard practice was that you could install a new layer of singles directly over the old layer during a re roof. Re roofing options to tear or not to tear off.

Asphalt shingles can be laid over cedar shakes or shingles however this is a roofing project best left to pros. Re roofing used to be pretty straight forward with 3 tab shingles.