Skylights are cool addition to the house…until they start leaking. A leaky skylight can suck the romance out of a skylight quicker than Roseanne can suck the romance out of a love story.
The first step in troubleshooting a skylight that is ruining its romance by leaking is to make sure that the leak is not just a result of condensation building up excessively. If you live in colder climates, condensation that runs along the underside of the glass before dripping down the side of the interior opening of the skylight is a common problem. The next step in skylight repair is ensuring that your window is completely closed. Check the weatherstripping seals to make sure they aren’t damaged, pulling loose or slipping open. Checking the sealing of your skylight is very much an important aspect of repair when the skylight is way on up there on the ceiling. Lower situated skylights are more easily inspected for faulty seals. Get yourself a ladder and an assistant and be very careful when checking the seals on a highly placed skylight.
Head outside and up onto the roof to get a good look for yourself at the condition of the skylight. Consider whether the leak seems to get worse during the colder months than it does during the warmer months. A skylight that leaks more often during the winter is actually a pretty good thing as far as troubleshooting. While you are on the roof, look around the skylight for a buildup of leaves or ice or even snow. Any kind of debris that serves to obstruct the gravitational pull of water down to your gutters and onto the ground below can be a cause of a leaky skylight. Debris like leaves or even an errant Frisbee lodged in the wrong place can result in water getting backed up under the shingles. From there, the route of the water to free itself will take it directly into the skylight and down onto your floor.
While up there on the roof, another method for troubleshooting a leaky skylight is to inspect the flashing all around the roof. Flashing is that metal stuff that you can find around vents or chimneys. Even if the flashing isn’t anywhere near the skylight that is leaking, you should inspect it to make sure it is sealed and in good condition. Water that gets under metal flashing can travel haphazardly across the length of the roof and eventually wind up leaking out of your skylight. So even if the flashing is on the opposite side of the roof, it is worthy of scrutiny and just might be troubleshot as the cause of your watery skylight problems.