HOME CLINIC — Repairing Asphalt Roofing Shingles -

HOME CLINIC - Repairing Asphalt Roofing Shingles -
By JOHN WARDE
Published: June 12, 1988

ASPHALT shingles, the most widely used roofing material in the United States, ordinarily last 15 to 25 years before needing replacement. Roofs with asphalt shingles should be inspected annually for wear if they are 10 or more years old. Leaks and damage to individual shingles must be repaired immediately.

The best way to inspect an asphalt roof is at close range. For safety, choose a day of fair weather, with no wind. Wait until morning dew has evaporated from both the ground and the roof, so that neither shoes nor shingles will be slippery from moisture. Wear sneakers, and have a helper brace the ladder while you climb.

Once on the roof, walk with knees bent to preserve balance and stay away from the building’s edges. A professional roofer will sometimes tie a rope around his waist and toss the free end over the roof peak to a helper on the other side. The helper then secures the rope to something solid, like a tree or porch railing.

To assess the overall condition of the shingles, notice whether areas seem dried out, cracked or worn. Shingles are coated on their top surface with fine gravel, which protects the asphalt from sunlight. If the gravel coating seems thin or is missing, this is an indication that a new roof may be needed.

Hunt for shingles that have curled upward or have become cracked or torn, damage usually caused by severe weather. These areas are often the source of roof leaks and must be repaired promptly. Choose a warm day with plenty of sunshine for repairing shingles, so the shingles will be pliable. Shingles that are cold and stiff may break.

A can of roofing cement and a flexible-bladed putty knife are essential supplies. To fix a curled shingle, sweep away dirt beneath it with a whisk broom. Then apply a generous dab of cement to the underside of the curled edges and press the shingle flat. Stand on the cemented portion for a moment or two until the cement sets enough to hold the shingle on its own. Be careful not to soil your shoe.

If the shingle continues to lift, weight it with a brick or other heavy object and leave it for 24 hours. Resist the temptation to nail the edges flat. Even if you cover the nailheads with roofing cement, which you must do, it is a roofers’ maxim that any openings created in a roof surface can become a source of leaks, no matter how well sealed.

However, to fix torn and broken shingles you must use nails. To mend a torn shingle from which no pieces are missing, brush beneath it, apply cement liberally to the underside, then press the shingle down while aligning the torn edges. Drive large-headed galvanized roofing nails along both sides of the tear, and also for several inches along the bottom edge of the shingle. Cover the nail heads completely by spreading a generous amount of roofing cement over them.

To repair shingles from which pieces have broken off, use a piece of aluminum or copper flashing material as a replacement patch. Flashing is available at building supply stores and some home centers. Cut the piece to form a rectangle, about three inches longer and wider on all sides than the area to be covered.

To install the patch, brush the area beneath the broken shingle free of dirt and coat it with roofing cement. Slide the patch into place beneath the broken shingle until the patch rests against the nails securing the shingle just above its vertical slits. The nail heads are hidden by the course of shingles that overlap the damaged one. Install flashing nails near the corners of the patch to fasten it. These must be of the same metal as the patch to prevent corrosion. Purchase the flashing nails where you obtain the flashing. Finally, cover the nail heads and the entire exposed perimeter of the patch with roofing cement.

If damage to a shingle is severe, or if several shingles in a group are broken, you may decide on replacement, rather than patching. Be sure beforehand that you can obtain new shingles to match the broken ones.

When replacing shingles, take care not to damage intact shingles nearby. Work only when shingles are warm and pliable. Begin by gently lifting the shingles overlapping the one to be replaced and prying out the nails securing the damaged shingle. Use a flat utility bar to remove the nails. Remaining nails are further toward the upper edge of the damaged shingle. Their heads are located beneath the shingles overlapping those just mentioned.

If you cannot pry the nails out without ruining undamaged shingles, cut the nails by sliding a hacksaw blade beneath the shingles and sawing them in two. Extract the nail heads or leave them in place, as you desire. However, you must flatten the stubs of the nails projecting from the roof surface beneath the shingles so that the new shingles will slide easily into place. To flatten the stubs, cover them with the tip of the utility bar and strike the bar with a hammer.

Slide the new shingle into place and align its lower edge with the shingles on both sides. Lift the overlapping shingles and install galvanized nails just above the shingle’s vertical slits, so that the overlapping shingles will cover the nail heads. Nail from one side of the shingle to the other to avoid wrinkling. Install the topmost row of nails in the holes from which the previous nails were withdrawn.

If you had to cut the nails and chose to leave the heads in place, install the new nails next to the old ones. To install new nails without damaging overlapping shingles, strike them indirectly, using the utility bar technique described. After the new nails are installed, apply roofing cement to all shingles that were lifted during the procedure.

To replace shingles at the roof peak, do not try to remove the damaged ones. Instead, spread roofing cement over them and position new shingles on top. Fasten each one at the corners with galvanized roofing nails at least two inches long. Cover the shingle seams and nail heads with roofing cement.

By JOHN WARDE
Published: June 12, 1988

ASPHALT shingles, the most widely used roofing material in the United States, ordinarily last 15 to 25 years before needing replacement. Roofs with asphalt shingles should be inspected annually for wear if they are 10 or more years old. Leaks and damage to individual shingles must be repaired immediately.

The best way to inspect an asphalt roof is at close range. For safety, choose a day of fair weather, with no wind. Wait until morning dew has evaporated from both the ground and the roof, so that neither shoes nor shingles will be slippery from moisture. Wear sneakers, and have a helper brace the ladder while you climb.

Once on the roof, walk with knees bent to preserve balance and stay away from the building’s edges. A professional roofer will sometimes tie a rope around his waist and toss the free end over the roof peak to a helper on the other side. The helper then secures the rope to something solid, like a tree or porch railing.

To assess the overall condition of the shingles, notice whether areas seem dried out, cracked or worn. Shingles are coated on their top surface with fine gravel, which protects the asphalt from sunlight. If the gravel coating seems thin or is missing, this is an indication that a new roof may be needed.

HOME CLINIC - Repairing Asphalt Roofing Shingles -

Hunt for shingles that have curled upward or have become cracked or torn, damage usually caused by severe weather. These areas are often the source of roof leaks and must be repaired promptly. Choose a warm day with plenty of sunshine for repairing shingles, so the shingles will be pliable. Shingles that are cold and stiff may break.

A can of roofing cement and a flexible-bladed putty knife are essential supplies. To fix a curled shingle, sweep away dirt beneath it with a whisk broom. Then apply a generous dab of cement to the underside of the curled edges and press the shingle flat. Stand on the cemented portion for a moment or two until the cement sets enough to hold the shingle on its own. Be careful not to soil your shoe.

If the shingle continues to lift, weight it with a brick or other heavy object and leave it for 24 hours. Resist the temptation to nail the edges flat. Even if you cover the nailheads with roofing cement, which you must do, it is a roofers’ maxim that any openings created in a roof surface can become a source of leaks, no matter how well sealed.

However, to fix torn and broken shingles you must use nails. To mend a torn shingle from which no pieces are missing, brush beneath it, apply cement liberally to the underside, then press the shingle down while aligning the torn edges. Drive large-headed galvanized roofing nails along both sides of the tear, and also for several inches along the bottom edge of the shingle. Cover the nail heads completely by spreading a generous amount of roofing cement over them.

To repair shingles from which pieces have broken off, use a piece of aluminum or copper flashing material as a replacement patch. Flashing is available at building supply stores and some home centers. Cut the piece to form a rectangle, about three inches longer and wider on all sides than the area to be covered.

To install the patch, brush the area beneath the broken shingle free of dirt and coat it with roofing cement. Slide the patch into place beneath the broken shingle until the patch rests against the nails securing the shingle just above its vertical slits. The nail heads are hidden by the course of shingles that overlap the damaged one. Install flashing nails near the corners of the patch to fasten it. These must be of the same metal as the patch to prevent corrosion. Purchase the flashing nails where you obtain the flashing. Finally, cover the nail heads and the entire exposed perimeter of the patch with roofing cement.

If damage to a shingle is severe, or if several shingles in a group are broken, you may decide on replacement, rather than patching. Be sure beforehand that you can obtain new shingles to match the broken ones.

When replacing shingles, take care not to damage intact shingles nearby. Work only when shingles are warm and pliable. Begin by gently lifting the shingles overlapping the one to be replaced and prying out the nails securing the damaged shingle. Use a flat utility bar to remove the nails. Remaining nails are further toward the upper edge of the damaged shingle. Their heads are located beneath the shingles overlapping those just mentioned.

If you cannot pry the nails out without ruining undamaged shingles, cut the nails by sliding a hacksaw blade beneath the shingles and sawing them in two. Extract the nail heads or leave them in place, as you desire. However, you must flatten the stubs of the nails projecting from the roof surface beneath the shingles so that the new shingles will slide easily into place. To flatten the stubs, cover them with the tip of the utility bar and strike the bar with a hammer.

Slide the new shingle into place and align its lower edge with the shingles on both sides. Lift the overlapping shingles and install galvanized nails just above the shingle’s vertical slits, so that the overlapping shingles will cover the nail heads. Nail from one side of the shingle to the other to avoid wrinkling. Install the topmost row of nails in the holes from which the previous nails were withdrawn.

If you had to cut the nails and chose to leave the heads in place, install the new nails next to the old ones. To install new nails without damaging overlapping shingles, strike them indirectly, using the utility bar technique described. After the new nails are installed, apply roofing cement to all shingles that were lifted during the procedure.

To replace shingles at the roof peak, do not try to remove the damaged ones. Instead, spread roofing cement over them and position new shingles on top. Fasten each one at the corners with galvanized roofing nails at least two inches long. Cover the shingle seams and nail heads with roofing cement.

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