How to Repair a Leaky Roof

Got a leaky roof? Water can do massive damage to a building's structural integrity, wiring and habitability. You can repair a leaking roof, however, by locating the source of the leak and applying the repair technique that is appropriate to your roofing material. Get out a pair of binoculars, don a pair of flat-soled shoes, and prepare to be very patient and methodical. The sooner you repair your roof, the more it will pay off in the long run in terms of water damage control.

Difficulty: Moderate

Instructions

Things You'll Need:

• Binoculars
• Flat-soled shoes
• Weighted markers for locating trouble spots on the roof
• Hammer and nails for marking trouble spots from inside
• Metal bristled brush for cleaning off trouble spots
• Rags for soaking up water
• Knife for peeling off old roofing cement or tar
• Roofing cement
• Trowel
• Roof patching fabric
• Gloves

Locate the Source or Sources of the Leak

1. Stroll around your house slowly with a pair of binoculars. Methodically inspect every square inch of your roof with the binoculars. Do you see any cracks, tears, or rot? These are often a leak source. Take note of where you see imperfections in the shingles or sheathing. Get up on the roof and mark the trouble spots with a weighted object that will not blow off. This first step is often easier with two people--one on the ground, another on the roof, communicating.

2. Walk around your roof with flat-soled shoes (so as not to further damage the shingles or sheathing) and look for further imperfections from an up-close-and-personal perspective. Mark trouble spots with a weighted object.

3. Inspect roofing features such as vents, skylights, chimneys and flashings. Do you see gaps? Broken cement seals? You will need to repair these places.

4. Get inside your attic and turn on a bright light or flashlight. Look around for water stains. Follow the winding trail of water stain to its most likely origination point. Use a hammer to poke a nail up through the trouble spot so you can locate it on the roof.

Repair All Possible Leaks

5. Repair any and all possible leaks originating from roofing features like vents and so on. Detach the roofing feature by unscrewing or prying it up. Clean off all the old cement or tar. Use a metal brush to scrape away all dirt and debris. Sop up any puddles of water using a rag and let dry.

6. Replace any roofing features (vents, etc.) you detached in Section 2, Step 1. Use a trowel to work roofing cement into all gaps. Overlap the cement by a couple of inches, feathering the cement into the roof shingles or sheathing so that water can drain off.

7. Repair any and all shingle leaks. Carefully peel up the edge of the shingle and work a broad patch of roofing cement over the trouble area. Remove any excess nails, replace them with new nails, and cover them with roofing cement.

8. Repair any and all rubber sheathing cracks. Apply a coat of roofing cement over the cracking, taking care to overlap the crack by a couple of inches. Embed a piece of roof patching fabric into the cement, apply another coat of cement, and you're done.

9. Repair any and all blisters, bubbles, or warping in the roof sheathing. Use a razor or carbide blade to cut an "X" in the trouble area, taking care to span the cut all the way to the edge of the warp. Peel up the resultant flaps. Apply a good layer of roofing cement under all the flaps. Be thorough. Cover the cement back over with the flaps, flattening them as much as possible. Apply more cement on top of the "X" and embed some patching fabric. Then another layer of cement, then another layer of fabric, and one final layer of cement. Feather the last layer of cement into the surrounding material to allow for water drainage.

Tips & Warnings

• Use gloves to keep your hands from getting covered in stubborn roofing cement. You can use penetrating oil (a popular brand is WD40) to clean off any cement that gets on your body.
• Always use flat-soled shoes when walking on a non-metal roof. This will prevent further damage.
• Cold weather makes shingles brittle, which makes them tend to crack or break. Hot weather increases the chances that your shoes will make damaging imprints on the roof material. Choose a mild day to work, if possible.
• Beware of rotten roof framing, and step carefully while on the roof.
• Never go on a roof intoxicated.