You can save money by inspecting your roof regularly to spot incipient problems. And you can save more by making simple repairs yourself.

Be Careful

You won’t save money if you injure yourself or damage your roof. A few tips:

If your roof is steep or made of wood or slate, stay off it—you could fall or break shingles.

Even if it’s safe to walk on, stay off your roof as much as possible. It is easy to crack shingles or pull out nails, particularly if shingles are warped. Much of the repair work roofers do takes place shortly after TV antennas or satellite dishes are installed or removed. Some disreputable roofers take advantage of the damage from careless roof-walking: They come out for a minor repair, or offer a free inspection, and predict that you will need a completely new roof soon. By walking roughly on the roof, they ensure that their prophecies are soon fulfilled.

If your roof is safe to walk on, wear soft rubber-soled shoes.

Don’t work on the roof in wet or windy weather. A wet roof or ladder can be dangerously slippery, and wind can easily knock you off balance. Make sure you don’t have wet grass or mud on your shoes.

Don’t put your weight on loose shingles or weak spots where you might put a foot through.

Make sure neither you nor your ladder touches a power line.

Lift your ladder carefully, and position it properly. Put the bottom end against the house; from the top end walk toward the house lifting the ladder over your head until you reach the house and the ladder is upright; then move the bottom end away from the house about one-fourth of the ladder’s length. To make it easier to step off of and onto the ladder, extend the top of the ladder at least three feet above the edge of the roof.

Climb the ladder by stepping onto the center of each rung, with both hands on the sides of the ladder. Tie off the ladder to the gutter to prevent it from being blown over.

When replacing damaged shingles, make sure the newly installed shingles lay flat over older ones. Also, try not to over-bend existing shingles that do not need to be replaced. If you bend shingles too much, they’ll crack or split, and you will have to replace them also.

Be Vigilant

Inspect your roof annually and after major storms, even if you don’t notice leaks.

If you have an unfinished attic, look inside it for evidence that water has come into contact with the rafters or sheathing. Poke at dark spots to determine if they are rotten. Examine areas where vent pipes, chimneys, skylights, or other elements pass through the roof. If you spot a hole in the roof, jam a length of wire up through it so you can find the hole from the outside.

If you have a finished attic, look for signs of water damage on the ceiling and walls. But know that the location of the damage may be far from the leak that caused it. Water often passes through a leak and runs along rafters, dripping off only when it hits an irregularity or obstruction. Only an outdoor inspection will let you spot problems you can’t locate from inside.

Begin an outdoor inspection by checking gutters and the foundation area for fallen shingles. Then look over the roof for missing or damaged shingles (you may be able to do this from the ground with binoculars). If you see water damage on an inside ceiling or wall, try to locate the point on the outside immediately above this damage, and then carefully work back and forth up the roof looking for the culprit leak. Check that flashings around chimneys, vents, and other protrusions have not developed holes or pulled loose.

Temporary Solutions and Repairs

If you discover a leak, temporary remedies are simple. Among the options: an emergency patch with roofing cement, applied generously; for shingle roofs, sliding a piece of galvanized steel, copper, or aluminum under the shingle above the leak, making sure the patch is large enough to carry the water away from the leak.

There are also permanent repairs that some homeowners can comfortably make:

Shingles: If you find loose asphalt composite shingles, remove loose nails, drive in new ones; then cover the old holes and the heads of the new nails with roofing cement. If asphalt composite shingles are merely warped, hold them flat with a spot of roofing cement about the size of a quarter.

Replacing a shingle, if necessary, is more difficult. Very carefully lift the shingles that lie over the bad shingle, remove the nails holding the bad shingle, remove the shingle, insert a new one, and replace the nails.

Flashing: Many cracks in flashing can be repaired, temporarily at least, with a layer of roofing cement. Cement can also be used to fill small joints where flashing has pulled loose from a chimney; simply scrape out the old mortar or cement, put the flashing back in place, and fill the joint with cement.

Moss and Algae Damage: Moss or algae growth can be a problem for some roofs, particularly wood-shingle ones. When moss or algae grows on a roof, it holds in moisture and can cause shingles to rot. Moss also can work down to the sheathing, causing structural deterioration. You can remove moss or algae growth by applying a commercial cleaner with a garden hose and/or by using a power washer.

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