Before starting a repair, locate shingles of the same type, color, and size of the existing shingles to replace those that have been damaged.

Lift the tab above the shingle that has been damaged and pry out the nails that hold the one you want to replace. Snip off the top corners of the replacement and slide it up under the existing shingles, being careful not to tear the roofing felt.

Nail on the new shingle, placing the nails under the shingle above. After driving in the nails, daub the nail heads with roofing cement.

While you are on the roof, check the roof flashing for corrosion or pinholes and repair with roofing cement (you may need to lift up a flap of shingles to get access to the flashing).

1) On a warm day, lift shingles to expose nails of damaged one. Pry out nails.
2) Slip replacement in place under up-roof shingles.
3) Nail by hammering against a prybar placed on nail heads.

Beneath the asphalt shingles on a roof’s surface, you’ll find roofing felt, sheathing, and the roof’s structure.