Leaky Roof Overview
If you have a leaky roof, you'd better fix it immediately, even if it doesn't bother you much or you're getting a new roof next year. Even over a short time, small leaks can lead to big problems, such as mold, rotted framing and sheathing, destroyed insulation and damaged ceilings. The flashing leak that caused an expensive repair bill was obvious from the ceiling stains for over two years. If the homeowner had dealt with it right away, the damage and subsequent repairs would have been minimal.
How to Find Roof Leaks
When you're trying to track down a leak, start by looking at the roof uphill from the stains. (Plus: here's how to clean roof stains.) The first thing to look for is any roof penetrations. Items that penetrate the roof are by far the most common source of leaks. In fact, it's rare for leaks to develop in open areas of uninterrupted shingles, even on older roofs. Penetrations can include plumbing and roof vents, chimneys, dormers or anything else that projects through the roof. They can be several feet above the leak or to the right or left of it.
If you have attic access, the easiest way to track down a leak is to go up there with a flashlight and look for the evidence. There will be water stains, black marks or mold. But if access is a problem or you have a vaulted ceiling, you'll have to go up onto the roof and examine the suspect(s).
A Trick for Finding Difficult Leaks
Solution for a Small Leak
Some roof leaks are tough to locate. Sometimes the water shows up at a ceiling spot distant from the leak. If your ceiling has a plastic vapor barrier between the drywall and the attic insulation, push the insulation aside and look for flow stains on the plastic. Often water runs to openings in the vapor barrier, such as at ceiling light fixtures.
If you can't see any telltale flow marks, and since the stain is fairly small, look at the underside of the roof for 'shiners.' A shiner is a nail that missed the framing member, in this case when the carpenter nailed the roof sheathing to the rafters. Moisture that escapes into the cold attic from the rooms below often condenses on cold nails. Sometimes you can spot this if you climb up into your attic on a cold night. The nails will look white because they're frosted. When the attic heats up a bit during the day, the frost melts and drips, then the nails frost up at night again and so on. The solution is to simply clip the nail with a side-cutting pliers.
Fix Plumbing Vent Boots
Plumbing vent boots can be all plastic, plastic and metal, or even two-piece metal units. Check plastic bases for cracks and metal bases for broken seams. Then examine the rubber boot surrounding the pipe. That can be rotted away or torn, allowing water to work its way into the house along the pipe. With any of these problems, you should buy a new vent boot to replace the old one. But if the nails at the base are missing or pulled free and the boot is in good shape, replace them with the rubber-washered screws used for metal roofing systems. You'll find them at any home center with the rest of the screws. You'll have to work neighboring shingles free on both sides. If you don't have extra shingles, be careful when you remove shingles so they can be reused. Use a flat bar to separate the sealant between the layers. Then you'll be able to drive the flat bar under the nail heads to pop out the nails.
Fix Roof Vents
Fix Walls and Dormers
Water doesn't always come in at the shingled surface. Often, wind-driven rain comes in from above the roof, especially around windows, between corner boards and siding, and through cracks and knotholes in siding. Dormer walls provide lots of spots where water can dribble down and enter the roof. Caulk can be old, cracked or even missing between the corner boards and between window edges and siding. Water penetrates these cracks and works its way behind the flashing and into the house. Even caulk that looks intact may not be sealing against the adjoining surfaces. Dig around with a putty knife to see if the area is sealed. Dig out any suspect caulk and replace it with a siliconized latex caulk. Also check the siding above the step flashing. Replace any cracked, rotted or missing siding, making sure the new piece overlaps the step flashing by at least 2 in. If you still have a leak, pull the corner boards free and check the overlapping flashing at the corner. Often, there's old, hardened caulk where the two pieces overlap at the inside corner.
Complex Roof Problem
This roof leaks during the snowy part of winter and during storms in the summer, certainly due to poor flashing. The soffit that meets the roof is one of the toughest areas to waterproof. In the photo, you can still see signs of an ice dam. An ice dam occurs when snow melts and the water freezes when it hits the colder edges of your roof. Eventually, water pools behind the dam and works its way back up under the shingles and under the soffit until it finds an opening through the roof.
The solution begins with good flashing, since this should stop leaks from rainfall and might stop the leaks from ice dams as well. Begin by removing the shingles down to the wood sheathing and slip a strip of adhesive ice-and-water barrier (available where roofing products are sold) 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 at least 2 in.
If leaks continue to occur from ice dams, consider installing roof edge heating cables. (Find them locally at hardware stores or home centers.) Improved attic insulation and ventilation are usually the best ways to prevent ice dams, but they might not be effective in this complicated roof situation.
Fix Step Flashing
Step flashing is used along walls that intersect the roof. 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 it goes. Rusted flashing needs to be replaced. That means removing shingles, prying siding loose, and then removing and replacing the step flashing. It's that simple. But occasionally a roofer forgets to nail one in place and it eventually slips down to expose the wall. Check out this article for more on installing your own step flashing.
Don't Count on Caulk!
Rarely will caulk or roof cement cure a roof leak?at least for very long. You should always attempt a 'mechanical' fix whenever possible. That means replacing or repairing existing flashing instead of using any type of sealant. Only use caulk for very small holes and when flashing isn't an option.
Fix Small Holes
Tiny holes in shingles are sneaky because they can cause rot and other damage for years before you notice the obvious signs of a leak. You might find holes left over from satellite dish or antenna mounting brackets or just about anything. And exposed, misplaced roofing 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 one with flashing.
Leaks Around Brick Chimneys
All kinds of bad things can happen around brick chimneys. In fact, there are far too many to cover in this story. Flashing around chimneys can rust through if it's 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. The best fix, though, is to cut a saw kerf into the mortar and install new flashing. Get complete instructions on how to install chimney flashing.
One way to make sure your gutter doesn't fall off the house is to install fascia hanger brackets. Installation is simple: Just hook the bracket under the front lip of the gutter, and then screw the other side of the bracket to the fascia. Leave the old spikes in place—a spike head looks better than a hole in the gutter.
If your shingles overhang your fascia by a few inches or you have steel roofing, buy the brackets with the screws built in (the type shown here). They cost more, but the head of the screw remains a couple of inches away from the fascia, making them a lot easier to install.
Water Gets Behind the Gutter
If water is dripping behind your gutter, it's probably because it was installed without any flashing over the back of the gutter. Gutter apron will prevent the dripping.
Gutter apron is a bent piece of flashing that tucks up under the shingles and over the gutter. Home centers sell it in 10-ft. sections. You may have to temporarily remove your hangers as you go, or you can notch out the apron around them. Once the apron's in place, fasten it with sheet metal screws.
If there's a drip edge installed where the fascia meets your shingles and the gutter is hung below the drip edge, get some roll flashing and tuck it up under the drip edge and over the top of the gutter. Home centers sell rolls of 6-in. x 10-ft. aluminum flashing. Use a tin snips to cut the roll in two 3-in. strips. If your gutters are steel, buy steel roll flashing, because galvanized steel corrodes aluminum.
Is the sound of dripping in your downspouts driving you mad? Eliminate the problem by tying a rope onto one of the gutter hangers and running it down into the downspout. Drops of water will cling to the rope instead of plummeting the whole length of the downspout and causing that loud dripping noise.
Adding a rope does restrict water flow, so this may not be the best option if your gutter is prone to overflowing or if your downspout is easily clogged with twigs and leaves. Buy a rope made of a synthetic like nylon—a rope made from natural fibers will rot away.
Make Repairs With a Slip Joint
If a tree branch falls on the last 4 ft. of your 60-ft. seamless gutter, you don't need to replace the whole thing; just replace the damaged section. If your gutters are white or brown, adding a section of gutter to an existing section is easy. Most home centers sell white and brown sections of gutters as well as slip joints to tie them together.
If your gutters are a custom color, a home center can special-order your color but not the slip joint to match. But don't worry; you can make your own from a box miter, and box miters are available in every color gutters are made.
When you buy your new gutter section, make sure you order either an inside or outside box miter at the same time. Cut a 3-in. section from the box miter with a tin snips, and you've got yourself a custom slip joint. Hang the new gutter next to the old one, and then slide the patch under the seam.
Water Spills Over Gutter
Some roofs have long sections of valley that carry a lot of rainwater at high velocity. When that water comes blasting out the end of the valley, it can shoot right over the gutter. A diverter will help direct the water back into the gutter where it belongs. Fasten a diverter with a couple of sheet metal screws to the top of the outside edge of the gutter.
Downspout in the Way
Are you tired of removing your downspouts every time you mow? Consider installing a hinge where the lowest elbow meets the section of downspout that runs into your yard.
Installation is simple: Just cut the downspout at a 45-degree angle with a tin snips or metal-cutting blade and fasten the two-piece Zip Hinge (sold at home centers or online) with eight sheet metal screws. The hinges come in white only, so you might have to spray-paint them to match.
Every connection on a metal gutter needs to be sealed: end caps, splices, drop outlets and miters. Buy a product that's specifically formulated to seal gutter seams. Seam sealer can handle submersion for long periods of time. It's also resistant to light, which it will get plenty of.
Most important, high-quality seam sealer is runny, so it can penetrate down into the seam for a durable, long-lasting connection. Most products refer to this property as “self-leveling.” And the runnier the better, so if you're applying it on a cold day, keep the seam sealer somewhere warm so it stays fluid.
Try to remove as much of the old sealer as you can, and make sure the area you're sealing is completely dry. Home centers usually stock seam sealer near the gutter parts.
If you have a 50-ft. gutter with one 2 x 3-in. downspout, your gutter probably overflows during heavier rainfalls. When installing an additional downspout isn't an option, install a 3 x 4-in. downspout in place of the smaller one.
Start by removing the old downspout. Use the new 3 x 4-in. drop outlet that you buy with your new downspout as a template to trace an outline for the larger hole. You can cut out the larger hole with a tin snips, or you could use an oscillating multi-tool equipped with a metal-cutting blade. Insert the drop outlet in the hole and fasten the new downspout with sheet metal screws. Make sure to seal the drop outlet to the gutter with seam sealer.
One downspout, one drop outlet, three elbows and two wall clips will cost about $40 at a home center. If you need a color other than white or brown, it will be a special order, but you should be able to get the color you need.
Sidewalk in the Way
There is no perfect way to get water from one side of a sidewalk to the other, but consider installing a retractable downspout. It rolls out when it rains and then rolls back up when the water stops flowing. Products like these do leak when the water flow is too light to extend the plastic downspout, but they should keep your landscaping from washing away during moderate to heavy rains.
Retractable downspouts are super easy to hook up, and they might be just the solution you're looking for. Pick one up at a home center or order online.
Gutter Guards Work
If you have trouble keeping small leaves and other debris from clogging your gutters, consider installing solid gutter guards. Solid guards, which cover all of the gutter except for a narrow crack to let the water through, do work well. The lip on the guards relies on surface tension to draw the water down into the gutter, while the solid covering deflects leaves and other debris that would otherwise drop in.
The guards work on every type of gutter, except plastic “C” shapes. Since the guards fit over the gutter rather than inside, they'll cover most standard-size gutters. They're typically attached to the gutter with brackets, with the upper edge slid under the lower shingles.
Screened gutter guards, which are much less expensive and available at home centers, don't work as well. They'll keep out most leaves, but you can expect smaller debris, such as seeds and pine needles, to get through. Screens also make gutter cleaning more difficult, because you have to move them aside to get at the debris. However, in some cases they may be all you need.
An old plastic spatula makes a great tool for cleaning debris from gutters! It doesn't scratch up the gutter, and you can cut it to fit gutter contours with snips. Grime wipes right off the spatula too, making cleanup a breeze.
Rusting Metal Gutters
Gutter leaks usually start at rusty spots or seams that have opened up because of expansion and contraction. If your gutter is still basically sound, the easiest way to stop the leak is by covering the damaged area with roof and gutter repair tape (available at home centers and hardware stores).
Prepare the gutter by scraping out as much old tar or caulk as possible. Wire-brush the metal thoroughly to get rid of rust and to give the tape a clean surface for bonding (Photo 1). If the gutter is badly rusted or has been heavily coated with tar that you can't scrape out, spray on a special adhesive primer before applying the tape (Protecto-Tek is one brand, but you may need to special-order it).
Cut the tape with a scissors or a razor knife (Photo 2). Tear the paper backing off the tape and lightly adhere one edge of the tape to the top of the gutter. Roll the tape down the wall of the gutter, pushing it firmly into curves and corners (Photo 3). Work wrinkles and bubbles flat. Overlap long seams by at least 1 in. and end seams by 4 in.