Prevent Leaks from Gutters

LESLIE: Doug in South Carolina, what’s going on at your Money Pit?

DOUG: Yeah, I was wondering if you can – if a leak inside the house can be caused by insufficient gutter size and, basically, what we have is a two-story great room and the water seems to leak down the wall in the great room and then kind of leak down onto the floor and it almost runs down the wall. And I’ve been up in the attic and the rafters, the roof rafters, seem dry. The only thing I think it can be coming from is the gutters, maybe, are not sufficient to hold the water.

LESLIE: Well, it could also be that there aren’t sufficient downspouts for that expanse of wall.

DOUG: OK.

TOM: Yeah, you need one downspout for about every 600 hundred square feet of roof surface. Assuming we’re talking about a six-inch K-style gutter, which is sort of your average gutter size, you …

DOUG: Yeah, it’s the average gutter size.

TOM: You need one downspout for every 400 to 600 square feet of roof surface and yes, if your gutters are blocked or if you have insufficient spouts, the water can back up in the gutters and get in under the roof. Ice & Water Shield is one of the roofing underlayment products that will stop that from happening – it’s made by Grace – but it’s not easy to put this on after the roof is up. So the first thing I would do is make sure you have adequate downspouts for this.

DOUG: OK, good. That’s what I – maybe I’ll put a downspout right in the – because it’s actually picking up – the one valley is picking up two sides of the roof; so you’re right …

TOM: Yeah.

DOUG: … I may not have enough gutter.

TOM: Yeah, then you can just add an additional spout and you may have to repitch the gutter so it goes down to both sides. But when you get situations where one roof is dumping to the next, very often that last spout is not picking it up. And the other thing that you could do is you could replace the four-inch spout with a six-inch spout. You may have to do a little fancy aluminum work to make it fit but you could just make a bigger downspout and that will cart more water away. But one way or the other you need to make sure that that gutter system is draining everything the roof is dumping on it.

DOUG: Sounds better than replacing a ceiling inside. (Leslie chuckles)

TOM: Absolutely. Doug, thanks so much for calling us at 888-MONEY-PIT.