How To Install Roofing Shingles Over Existing Roof

So if there are already two layers the choice is made for you.

How to install roofing shingles over existing roof.

The felt should be secured every six inches with nails or staples. Start by laying asphalt felt or other underlayment over the roof. Damaged decking will need to be repaired before you can install any new shingles. Damaged shingles should be removed to check the decking for problems.

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. To vent the roof holes are cut in the old roof above the soffit which pulls air through the soffit vents underneath. Install a layer of roofing felt over the roof before you begin installing the new shingles. You need to tear off the roof and install a new one.

This is what it looks like when you install a steel shingle roof system over an existing asphalt shingle roof. Current shingles are curling or in bad shape the new shingle roof should lay flat on your old one. Use a starter strip or cut pieces for a starter course. Before you begin installing the new shingles be sure to inspect the roof for any damage.

Install new shingles to the lower edge of the opening. Using your staple gun secure the felt to the roof. If you nick or tear the old flashing piece then go buy a new one. Multiple layers of shingles can make it difficult or impossible for the nails to penetrate.

Step 3 cover the old shingles. 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. Overlap each row at least 3 to 4 inches.

Attach with nails along the top edge of the strip. Inspect the condition of your current roof. Remove the cover and then nail the old shingles back down again. The condition of the existing roof is critical.

But if the current roof is curling this isn t possible.