Fixing a Leaky Skylight

LESLIE: Next up, we’ve got Joan who’s got a leaky window. Tell us about the problem.

JOAN: It’s not really a window. It’s a skylight. It leaks around it into the attic and I’ve put a pan under it but I’d like to be able to fix it.

TOM: Well, tell us what type of skylight this is. Does it sit up off the roof a few inches?

JOAN: Right. Uh-huh.

TOM: OK. And how old is it, Joan?

JOAN: Ten, 15 years?

TOM: Alright. Well, typically what happens to the curbed skylight – that’s called a curbed, c-u-r-b-e-d, a curbed skylight –

JOAN: Uh-huh.

TOM: With a curbed skylight, they rely on sealants to become watertight between the skylight itself and the roof and typically those sealants will break down and it has to be reflashed. To do that you’re going to have to have a roofer take the shingles off that are around it and then reseal it to the roof. It essentially has to be reset; unless there’s some obvious reason that it’s leaking, like a broken shingle or something of that nature. If it’s just a breakdown of the skylight as it adheres to the roof, then it probably needs to be reseated.

There’s one other trick of the trade that we can give you. If this skylight happens to have a lot of roof above it – in other words, if it’s not right near the top of the roof so you get a lot of rain that runs down and strikes it – you can install something called a diverter which is a piece of metal bent into a 90-degree angle that sits right on top of the skylight. And the purpose of the diverter is to collect the runoff that comes streaming down that roof really fast and run it around the skylight a bit. It’s the same thing that’s done when you have a roof that goes into a chimney. In that case it’s called a cricket. But you simply can construct a diverter and attach it to the roof with a couple of nails and seal underneath and that will stop the volume of water from coming up to it. And I think there’s a lot better ways to do it than sticking that pan under it and that should solve it for you.

Joan, thanks so much for calling us at 888-MONEY-PIT.