Is your roof leaking and causing water stains on your walls and ceilings? Don’t panic! Most leaks are easy to fix and take only a few minutes to repair. Here are 12 tips for fixing common roof leaks yourself:
1. Start by locating the source of the leak
The first step in fixing a leaky roof is to locate the source of the leak. Start by looking uphill from the stains on your walls or ceiling. Penetrations like chimneys and roof vents are the most common culprits. Look for any signs of damage, such as cracked or missing flashing, and check for gaps around the penetrations where water can seep in.
2. Use a garden hose to isolate the leak
If you can’t find the source of the leak, enlist a helper and use a garden hose to isolate the area where the leak might be. Start low and work your way up the roof, soaking the area just above where the leak appears in the house. Isolate areas when you run the hose, and have your helper stay inside the house waiting for the drip to appear. Let the hose run for several minutes in one area before moving it up the roof a little farther. This process can take well over an hour, so be patient and don’t move the hose too soon.
3. Check for small leaks with flow stains
If you have water stains but can’t see any obvious signs of damage, look for flow stains on the plastic vapor barrier between the drywall and the attic insulation. These stains can indicate small holes in the roof that have been slowly causing damage for years. You can fix this problem by using flashing instead of caulk to patch the holes and prevent further damage.
4. Fix plumbing vent boots
Plumbing vent boots can be a common source of roof leaks. Check for cracks in plastic bases or broken seams in metal ones. Examine the rubber boot surrounding the pipe, which can be rotted away or torn, allowing water to work its way into the house. Use rubber-washered screws to replace missing or pulled free nails at the base of the boot if the nails are in good shape.
5. Repair cracked or broken roof vents
Cracked housings on plastic roof vents or broken seams on metal ones can also cause leaks. Don’t just throw caulk at the problem; replacing the damaged vents is the only permanent solution. Check for pulled or missing nails at the base’s bottom edge, and replace them with rubber-washered screws. You’ll need to remove neighboring shingles on both sides to work on the vent, but try to reuse them if possible.
6. Seal gaps around windows, corner boards, and siding
Water can also seep in through gaps around windows, corner boards, and siding. Caulk can be old, cracked, or missing between the surfaces, allowing water to penetrate and work its way behind the flashing and into the house. Dig around with a putty knife to see if the area is sealed, and replace any suspect caulk with high-quality caulk. If you still have a leak, pull the corner boards free and check the overlapping flashing at the corner.
7. Fix walls and dormers
Water can penetrate cracks and knotholes in siding, as well as between corner boards and siding, causing leaks around windows and dormers. To fix this, first check the caulking around the corner boards and between window edges and siding, replacing any old or cracked caulking with a high-quality caulking. If the area is not sealed, use a putty knife to dig around and check if the siding above the step flashing is cracked, rotted, or missing. If it is, replace it with new siding and make sure it overlaps the step flashing by at least two inches. If the leak persists, pull the corner boards free and check the overlapping flashing at the corner. Often, there’s old, hardened caulking where the two pieces overlap at the inside corner.
8. Complex roof problems
If you experience leaks during both the snowy part of winter and storms in the summer, it could be due to poor flashing, especially at the soffit that meets the roof. The solution begins with good flashing, which should stop leaks from rainfall and might also prevent leaks from ice dams. Remove the shingles down to the wood sheathing and slip a strip of adhesive ice-and-water barrier under the soffit/main roof joint. Depending on how the roofs join, you may have to cut a slot to work it in far enough. It should overlap another piece of ice-and-water barrier laid below, all the way down to the roof edge. This should cover the most leak-prone areas. Then reshingle, sliding metal step flashing behind the fascia board (the trim behind the gutter). The valley flashing, laid over the joint where the two roofs meet, should overlap the step flashing by at least two inches. If leaks continue to occur from ice dams, consider installing roof edge heating cables. Improved attic insulation and ventilation are usually the best ways to prevent ice dams, but they might not be effective in this complicated leaky roof situation.
9. Fix step flashing
Step flashing is used along walls that intersect the roof, and each short section of flashing channels water over the shingle downhill from it. But if the flashing rusts through or a piece comes loose, water will run right behind it and into the house. To fix this, remove the shingles, pry the siding loose, and then remove and replace the step flashing. Occasionally, a roofer may forget to nail one in place, and it eventually slips down to expose the wall.
10. Don’t count on caulk
Caulk or roof cement rarely cures a leaky roof for very long. It’s always best to attempt a “mechanical” fix whenever possible, which means replacing or repairing existing flashing instead of using any type of sealant as a leak stopper. Only use caulk for very small holes and when flashing isn’t an option.
11. Fix small holes
Tiny holes in shingles can cause rot, a leaky roof, and other damage for years before you notice the obvious signs of a leak. Exposed, misplaced roofing repair nails should be pulled and the holes patched. Small holes are simple to fix, but the fix isn’t to inject caulk in the hole. You’ll fix this leaky roof problem with flashing.
12. Leaks around brick chimneys
Brick chimneys are a common area where leaks can occur, and there are many potential causes. Flashing around chimneys can rust through if it’s made of galvanized steel, especially at the 90-degree bend at the bottom. A quick but fairly long-term fix is to simply slip new flashing under the old rusted stuff. That way, any water that seeps through will be diverted. However, the best solution is to cut a saw kerf into the mortar and install new flashing. It’s essential to get complete instructions on how to install chimney flashing properly to ensure that the leak is effectively resolved.
With these 12 tips, you should be able to track down and fix most types of roof leaks without the need for professional help. However, it’s crucial to note that safety should always come first, and you should never attempt to climb onto a roof without the appropriate safety equipment and training. If you’re not confident in your ability to handle the repair yourself, it’s best to call in a professional roofer to ensure that the job is done correctly and safely.
