Fix roof leaks and minor repairs

Know which repairs you can make yourself, and when it's best to call a professional.

Before you get started

Roofing manufacturers are usually very specific about how repairs should be made to their products. Take nails, for example. Most manufacturer’s installation instructions specify what size nail should be used, and warranty coverage may depend on how many nails are used to install each shingle.

Check your manufacturer's warranty and installation instructions before starting a do-it-yourself roof repair.

If you don’t see anything there, check the walls and windows - not all leaks come from your roof. If you don’t have attic access or your attic doesn’t have a full floor making it too dangerous to enter, you can head up to the roof — with plenty of caution — and look for these three common issues:

  • Damaged or missing shingles
  • Gaps on or near flashing material found around vents and other openings
  • Loose or deteriorating roof vent coverings

How to replace shingles

Damaged shingles should be removed and replaced.

  • To remove damaged shingles: Slide a pry bar under the shingle above it, then use a hammer to take out the nails of the broken one. Scrape the area to remove any roof cement left behind.
  • To replace a shingle: Gently lift the shingle above the one you want to replace, and align the new shingle underneath. Nail in the headlap so the shingle above covers the nail and hand seal the shingle. Finish with a trowel, by applying roof cement over the nails and each edge of the new shingle. Be sure to check the manufacture installation instructions for proper nail-size to use and how many nails are used to install each shingle.

Find a GAF Factory-Certified Contractor

At GAF, we train and test thousands of the best roofers in the country and make sure they're appropriately licensed and insured so they can offer our best warranties.