Installing New Roof Over Old Roof

The existing asphalt.

Installing new roof over old roof.

Find a pre screened local roofing contractor. 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. Installing a new roof over an existing one also called a layover or nailover is often possible although not always the best option. Can new plywood be installed on a 40 year old roof without removing the old.

Construction of a new roof deck for asphalt fiberglass roofing if you re going to add a roof on top of an old one it s a good idea to remove any loose shingles and apply a new layer of 30 pound roofing felt before laying the new shingles. Installing new roof shingles over old effectively doubles the weight of the roofing so you have to make sure your roof structure can handle the extra load. All shingle manufacturers honor the warranty whether their products are used for a reroof or a new roof. Manufacturers will still warranty the roof for the same amount of time as a re roof as long as it s done by a qualified installer.

Install a layer of roofing felt over the roof before you begin installing the new shingles. As long as it s done right and under the right conditions installing new shingles over old ones can last as long and look just as good as a complete re roof. The felt should be secured every six inches with nails or staples. Looks just as good and lasts as long.

A properly installed layover roof can look and function as well. But you must take care to install shingles correctly so they lie flat. I ll explain why later. Installation is easier than for a tear off job because you can use the existing shingles as guides for laying the new ones.

Or if you want to raise the roof a bit more install fascia around the roof perimeter attached to the new soffit and nail the new roof deck to crown molding above the fascia. Roofing over your old roof can save you around 1 000 on installation costs because the roofing company won t have to remove and dispose of old shingles. Installing a new roof over shingles takes less time than tearing off the old roof. The layers of felt should be overlapped by 1 inch as you work toward the roof ridge.

This will help keep any moisture from getting under the felt. That s also why building codes commonly limit re roofing to no more than two layers. It can save you money at the time but it might actually end up costing you more in the long run. Has the same manufacturer s warranty.