How Do You Roof Over With Composition Shingles?
If your house needs a new roof and the structure of the building is above average, it may be possible to roof over the existing roof with composition shingles. You follow the same procedure as you would if the old roof were removed first. The only difference is that you are applying the composition shingles directly on top of existing shingles, rather than over wood or rubber membrane. This type of roof usually has a useful life of 20 to 30 years. Check over the existing shingles looking for any nails or nail heads that rise above the surface level. Drive them back into the roof. Remove any shingles that are warped or buckled. Begin at the eave edge of the roof. The first row of composition shingles are always installed so the top edge is even with the eave edge of the roof. The top edge of a composition shingle is the straight, unnotched edge. Place a shingle even with the edge of the roof and place three nails into the nailing area. The nailing area is indicated by a band of resinous
