Building and city codes require roofers to limit shingle layers to two. Nonetheless, roofers working on older houses sometimes find shingle layers as high as four. This method of shingling does cut down on costs of excavating existing shingles but causes a strain on the house between the trusses.
Building and city codes require roofers to limit shingle layers to two. Nonetheless, roofers working on older houses sometimes find shingle layers as high as four. This method of shingling does cut down on costs of excavating existing shingles but causes a strain on the house between the trusses.
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