Roof leaks can be cause by missing shingles, gaps in the metal flashing around chimneys and vent pipes, or small holes in the roofing. The source of a leak often isn’t obvious on the roof itself, and it can be hard to pinpoint, since the water may run down the roof decking and rafters before dripping onto the ceiling below.
To locate a hard to find roof leak:
- Go in the attic with a flashlight, during or shortly after a heavy rain, being careful not to step through the ceiling. In the absence of rain, use a garden hose to thoroughly wet down the roof to create a manmade leak.
- Examine the roof decking and rafters in the attic above the spot where the ceiling is wet.
- Follow any water stains or wet spots up the rafters or roof decking to their highest point.
- Measure down from the roof peak to the highest point of the leak and over from a gable end to the leak.
- When the roof is dry, go on the roof, and transfer the measurements to the roof, allowing for any overhang on the end of the roof.*
- Examine the roofing closely for signs of the leak at the location you measured.
- If you can’t see the source of the leak, continue to look higher up on the roof, since water can run down behind the shingles before emerging in the attic decking or rafters.
*NOTE: Take all safety precautions when positioning ladders and climbing on a roof, and do not attempt to go up on a steep roof.
Watch this video to find out more.
- The Search for Hidden Roof Leaks (article)
- Cleaning and Inspecting a Roof (video)
- How to Find Roof Leaks (video)
- Repairing an Asphalt Shingle Roof (video)
Danny Lipford: On a day like this when the spring showers are moving in, you can feel pretty good about having a roof over your head. Unless, of course, you’ve got a pesky roof leak that you just can’t find.
There could be a problem with flashing, or maybe a shingle was torn off during a storm. Either way, you still have to find and repair the problem. If you can’t find it from the outside, let me show you some of the things you can look for on the inside.
In most cases, you find out about a roof leak by seeing a water stain on your ceiling. To locate the source of the problem, go up into your attic and try to get above the stain in the ceiling.
If you’re really lucky, you can locate the problem right away, but that’s rarely the case. More often than not, the source of the leak is some distance away, but this is still the best way to get started in finding that leak.
Now, carefully examine the decking and rafters above the stain location. And what you’re looking for is a water trail or stain on the wood somewhere between this spot, that’s directly over the stain, and the peak of the roof.
Now in this case, you can see the stain very clearly. But if you have a little trouble finding a water trail, have someone spray water on the roof with a garden hose while you’re still in the attic.
Have them start at the lowest point of the roof and work their way up. Make sure they use a spray attachment on the hose to imitate rainfall.
Then, just be patient. Eventually, you’ll find the leak, make your repairs, and then you can enjoy the sounds of the falling rain.
What a great videos you have shared for finding roof leaks. It can be tricky task. Most roof leaks are hard to find because it originates away from where the leak shows up. Water typically comes in through worn, broken, or missing shingles; where nails have worked loose; or through corroded or poorly sealed roof flashing around vents, skylights, or chimneys or along the intersections of roof planes. If you can’t find the cause of a leak from the attic or by visual inspection on the roof surface, wait for dry weather and ask a friend to help you do a water test. Check for leaks in the spring and fall, and keep an eye out for strong storms. It’s important to catch leaks before they become major problems. Go into the attic and look for water lines or streaks. Most commonly they will appear around seams or in areas of the roof that have sustained some type of damage. Roofs can last for long and for decades only if proper maintenance and care is taken. Timely and effective measures can keep many roofing problems at bay. Thank you for sharing such a wonderful article. It was a good read.
Can water run up under roll roofing where this low pitch roofing laps shingled roof at the ridge pole?
We have tried everything to find the leak in the roof. It only leaks when we have a hard rain. We think it leaks around the chimney.
We had a very small spot showing up until Hurricane Harvey and then our ceiling caved in the exact same spot. I say it was the storm and my husband who climbs into the attic cannot find evidence of roof leaks and blames it on condensation from leaky AC tubes that lab over each other right at that spot. He thinks that one of them is leaking and I think the intensive amount of rain from Hurricane had to be the culprit. Ceiling collapsed during storm!!! What do you think?
We have a composite shingle roof with 7 skylights. I covered the entire roof with two coats of snow coat. (50 gallons) For two reasons, the heat in the summer and we had 3 leaks Being careful to seal around every pipe, sun tube and skylight. Hours making sure the thick coating was under the edge of every tile. This was over a period of two weeks in the summer. When I finished, one could see it was a monolithic seal from one side to the other. Beautiful. But only one small problem. I still have 3 leaks!!! So between downpours I went up and covered my skylights with plastic sheeting, thinking it must be somewhere in or around the top (Even though I sealed every possible point of entry with clear rubber coating) And guess what? I still have 3 leaks!! I’m having some minor chest pains now… I hope it something I had with breakfast……
Thanks for all the information, however, what do I do when I don’t have an attic. The water is leaking around an outside wall window. Thought it was a doorway above the window but lots of [plastic up there did not affect the leak.
I love to see all your show and have learn so… much. Thank you.
But, I’m re-coating my hypollanne roof after we pass a catergory 5 hurricane. Could you give some advice so there will be no leaks.
Again, thanks. I remain…
Several people said they couldn’t find my leak they think my leak cause my a rusty nail is that true.
Hi, Brenda! There’s a wide range of reasons why your roof is leaking.
We recommend using these tips (in the above video) to isolate the cause.
Unfortunately, it would be impossible to determine the cause without observing it first hand.
I think that I have a few leaks in my roof but I can’t find the source of the leak. It is great to know that I should try using a flashlight to try to find a hold in my roof. Personally, I would want to get a professional roofer to find those leaks for me quickly.
I have an ongoing leak in my bathroom ceiling. Each time the ceiling dries out, I repair it. House built in 1860 and is a 3 story Victorian/Empire style. The bathroom where the leak occurs, is on the 2nd floor. Above and outside is where the 2nd floor roof, meets the wall up to the third floor and this wall has a window. Like tiers of a cake for lack of a better description. Have tried caulking around the window, sealing where the window is and where it meets the wall and roof of the second floor and it seems that I get the leaks primarily after an intense storm. (btw, spend 13k on new roofing) and the roofer could never find it either).
We have a home built 3 years ago colourbond roof. Issue mould and water leak in two rooms bedroom and bath on one side of house. Told by builder t is condesation. Or laek Cause…… Waiting for a cold day with heavy rain to investigate may take months open for suggestions
just had a new garage and lean to built and went it rains in the lean to there is 2 constant leaks. dripping constantly when having heavy rain. My builder said it is condensation. But when we have no rain there is no problem. he has recently filled with insulation and expanding foam and the leak has now moved to a different section since doing this. I think it may be the guttering. Any advice
Great question! We have forwarded it to the Today’s Homeowner Radio Show’s producer.
He will contact you soon to discuss featuring it during an upcoming show.
Our roof only leaks in the winter with snow on it. Then we notice a wet spot on the ceiling. Do you think the best thing to do is to find a roofing contractor?
So strange, but a great question! We have forwarded it to the Today’s Homeowner Radio Show’s producer.
He will contact you soon to discuss featuring it during an upcoming show.