25

A lot of questions have been asked about how to locate a leak in a roof, but you can only locate a leak that you know exists, and the first noticeable sign that there is anything wrong might be drywall damage in your living space.

By this point, the drywall is obviously already damaged, and the roof decking or other behind-the-scenes parts of the house might also have significant damage, so you need to pay not only to repair the leak but to clean up the damage it caused.

If you knew about the leak when it first started, you might be able to repair the leak early enough that it wouldn't have time to damage anything else.

How can you monitor or screen for leaks or possible leak-causing damage in a residential roof, so that they can be fixed before they cause water damage?

interfect
  • 353
  • 3
  • 5

5 Answers5

17

I go up into my attic about once a month (or after we get a heavy storm) with a good flashlight and give everything a visual inspection. Specifically, I make sure I'm very accustomed to the way that the roof is supposed to look. Then, in the handful of cases where I've had a small leak, that leak stands out as pretty obvious.

Leaks generally start small and work their way up. When water first starts seeping in slowly, a lot of it gets absorbed by the wooden roof decking, the rafters, or if it drips down, by the wood on the attic floor. Wet wood is much darker than dry wood (insulation usually looks different as well), so I've always identified leaks by noticing the dark spot that wasn't normally there. If it's a leak, it'll usually be damp to the touch as well. You're technically not detecting the leak before it happens, but with regular inspections you can notice it before it has a chance to cause any real damage or make it through to the drywall. This is where it's important to know what your attic looks like under normal conditions, so you'll know that dark spot has always been there but that dark spot is new. Most leaks occur around places where there's already a hole in the roof (vents, chimneys, satellite dish mounts, etc.) so pay particular attention to those areas.

Again, it's not a perfect solution, but it's easy to do, free, only takes about 10 minutes, and is fairly effective.

bta
  • 2,123
  • 7
  • 15
8

Roof leaks are caused by many different things. For example:

  • Shingles or tiles: Cracked, broken, missing, worn
  • Flashing: Loose, broken, missing, poorly installed, worn
  • Gutters: misaligned, clogged
  • Ice dams
  • Flat roofs: insufficient or poorly spread gravel
  • All roofs: end of life

Most of these are difficult or impossible to detect directly. You need experience and expertise to be able to tell when normal wear leads to the need for spot repairs, total replacement, or when there are abnormal problems.

I know this isn't much of an answer but I think it's a really good question and unfortunately there isn't a magic answer. The best I have is: Read up on the particular kind of roof you have, know what KINDS of things can go wrong, understand that water travels, inspect it regularly so you are in tune with what "normal wear" looks like, and watch for stains or other signs of leaking. Have it professionally inspected once in a while, and learn from the person you hire to do that.

jay613
  • 49,543
  • 6
  • 70
  • 201
6

A visual inspection once a year or after a severe storm. A great pair of binoculars could save you trips to up on the roof. Look for any shingles that have lifted or are torn. Also look for nails that have started to come out, raised up from the singles, especially on the saddle shingles on the peaks. Once you detect flaws, fix them promptly. Unfortunately, most leaks are found by noticing a water stain on your ceiling. What you do then is put a pan in the attic over the spot to stop the water from soaking more into the ceiling and then start investigating where the water's coming from.

JACK
  • 89,902
  • 21
  • 80
  • 214
3

Whether you have a tiled roof, a sloped one or a flat one, the roof’s surface can suffer from persistent moisture which leads to damage.

Many causes for leaks, and none is predictable but some are obvious like Shingles: missing, cracked, broken, Flashing: Loose, broken, poorly installed, worn, Gutters: misaligned, clogged.

The challenge is by the time you can see it, it has already progressed. The leak damage is not always directly under the problem, it might leak somewhere else .

You can detect any leak well ahead of time using a thermal camera, that professionals use.

From inside (under the roof),

Or without climbing on the roof from outside with drone.

Additionally it could expose roof insulation problems (hot spots).

Not only the roof: Infrared is helpful for all home insulation checking. On Hot days with AC running full blast it can detect your hot spots. On Cold winter days it can detect your leaks.

If you are looking for renting or buying: Some typical average costs are $250-350 for regular visual inspection, $550 for an infrared drone roof inspection. Slate and tile roofs are harder to inspect and it costs an average of $800 for large roofs.

DIY visual inspection: If you do it from under the roof, you can only reach about 1/3 of the area (where you fit in). If you do it from outside (walking on the roof), you must use safety line or risk you life.

DIY75
  • 20,686
  • 3
  • 23
  • 47
2

Something I've learned the hard way is to get your roof inspected for the proper nailing pattern.

Nails should never fall in between butted shingles; I think they're supposed to be at least an inch from the butt but don't quote me on that.

MonkeyZeus
  • 17,328
  • 2
  • 27
  • 64