How To Install Roofing Shingles Over Existing Roof

The roof should be in sound.

How to install roofing shingles over existing roof.

Install a layer of roofing felt over the roof before you begin installing the new shingles. Damaged decking will need to be repaired before you can install any new shingles. The felt should be secured every six inches with nails or staples. 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.

Attach with nails along the top edge of the strip. These pieces act as a weather proofing and protective barrier between your house and the elements helping keep water and cold temperatures out. To vent the roof holes are cut in the old roof above the soffit which pulls air through the soffit vents underneath. If you nick or tear the old flashing piece then go buy a new one.

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. 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.

This is what it looks like when you install a steel shingle roof system over an existing asphalt shingle roof. The condition of the existing roof is critical. So if there are already two layers the choice is made for you. Overlap each row at least 3 to 4 inches.

Using your staple gun secure the felt to the roof. Install new shingles to the lower edge of the opening. Step 3 cover the old shingles. Remove the cover and then nail the old shingles back down again.

Cut the existing shingles and pry up carefully. Inspect the condition of your current roof. How to install a roof over an existing roof determine the feasibility. You need to tear off the roof and install a new one.

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