How To Install Roofing Shingles Over Existing Roof

Install a layer of roofing felt over the roof before you begin installing the new shingles.

How to install roofing shingles over existing roof. The felt should be secured every six inches with nails or staples. Multiple layers of shingles can make it difficult or impossible for the nails to penetrate. So if there are already two layers the choice is made for you. Before you begin installing the new shingles be sure to inspect the roof for any damage.

Inspect the condition of your current roof. Remove the cover and then nail the old shingles back down again. Use a starter strip or cut pieces for a starter course. Rip cut the starter strip or starter pieces so that they butt up against the second course of existing shingles and are even with the front edge of the existing roofing.

But if the current roof is curling this isn t possible. Using your staple gun secure the felt to the roof. The condition of the existing roof is critical. Attach with nails along the top edge of the strip.

Start by laying asphalt felt or other underlayment over the roof. Damaged shingles should be removed to check the decking for problems. Step 3 cover the old shingles. How to install a roof over an existing roof determine the feasibility.

Overlap each row at least 3 to 4 inches. To vent the roof holes are cut in the old roof above the soffit which pulls air through the soffit vents underneath. Install new shingles to the lower edge of the opening. Current shingles are curling or in bad shape the new shingle roof should lay flat on your old one.

If you nick or tear the old flashing piece then go buy a new one. These pieces act as a weather proofing and protective barrier between your house and the elements helping keep water and cold temperatures out. Cut the existing shingles and pry up carefully. The roof should be in sound.

There are already two layers of shingles on your roof most building codes only allow two layers of any type of roofing on your home.