Install a Curtain Drain to Keep a Basement Dry
LESLIE: Peter in California has had a leak in his basement. What happened?
PETER: Well, I live in a 20-year-old building and on one side of the basement wall is sheet rock, behind which is a solid, cement foundation wall of about 10 feet. And it started leaking so I took the sheetrock off and, lo and behold, when they poured the concrete, we have there what’s called a cold joint – that is, the workmen went home for the day halfway through the foundation and poured the second half the next day.
TOM: Right. Mm-hmm.
LESLIE: Ooh, so it didn’t actually join properly.
TOM: Yeah. Does it have like a gasket in between it?
PETER: No gasket. It was just …
TOM: Huh. Okay.
PETER: … the way they did it. So it leaks there and it’s been patched a hundred times with caulking …
PETER: … and cement. Leaks right through.
TOM: Well, what’s on the other side of that wall? Is it … is the yard out there?
PETER: A solid hill, dirt, rocks and a guy’s house with a (laughing) … a walkway I’d have to jackhammer through to get down to it.
TOM: Now is this solid hill with the guy’s house above grade? In other words …
TOM: … are you on the down side of this?
PETER: Above grade.
TOM: Alright. But I mean you’re on the down hill of it …
TOM: … I presume. Yeah. Well, I mean the problem here, Peter, is gravity. (laughing) And you, my friend, are on the wrong side of Isaac Newton’s equation. What you have to do is intercept that water before it gets to that space in the wall. And if it is solid concrete, you may actually have to break up some of that sidewalk. What I would do in a situation like this is something called a curtain drain, which basically is a trench, filled with gravel, that has a perforated pipe in it …
LESLIE: And it diverts the water away from the foundation and deposits it somewhere else.
TOM: Yeah, exactly.
PETER: The guy’s walk is about the level of my ceiling; so it’s up there.
TOM: Yep. Yep. And the water’s collecting against the wall. Now let me ask you this. What … do you have a gutter on the side of your house? And does he have a gutter?
PETER: No. No gutter. It’s the walkway and then it hits my house and there’s the foundation wall.
TOM: Well, wait a minute. Now, does your roof dump water on that sidewalk, too?
PETER: Yeah, the north side of the wall goes up three stories … up.
TOM: Well, that area – where his walk is –
TOM: – does … could your roof use a gutter in that space? And the reason I’m asking you this is if you can reduce the amount of water that’s going on the sidewalk …
LESLIE: That’s getting to that area.
LESLIE: You might solve this problem.
PETER: Be less water coming … and I … but, frankly, I’ve noticed when he waters his tree in his backyard …
TOM: That happens all the time.
PETER: Well, he left the hose on one night and, sure enough, it went down through the dirt …
PETER: … not the sidewalk; the dirt.
TOM: Yeah, it’s a water management issue, Pete. It’s not … you know, it’s not water coming up; it’s water falling down. So any place that you could try to collect that water. Now, certainly, if you don’t have a gutter on that side of your house …
LESLIE: Put one on.
TOM: … put one on. And intercept all the water that’s landing on the sidewalk.
LESLIE: And make sure that downspout isn’t put on the side where you have the problem.
LESLIE: Make sure that downspout goes somewhere else.
PETER: Is there anything I could put on my side of the wall to seal that crack?
TOM: Well, you could … I mean if you cleaned out all the old stuff and just got a good clean coat of silicone in there … a silicone caulk – which is probably the best sealer for concrete –
TOM: – but still, you know, you can put your finger in the dike (chuckles) but you can only hold back the water so much. So … but, really, anything you can do to reduce the flow against that part of the house is going to make a difference here. Including getting him to be a little more courteous with the sprinkling and putting a gutter on and things like that. But if you … if you have a situation where the house is so much higher than yours and all that water’s getting dumped on you, the hard core solution here is a curtain drain. And that will solve it. But it’s the most disruptive.
LESLIE: (overlapping) Now, what about that drywall in the basement. Was it up against that foundation wall or was there …?
PETER: Yeah. And I pulled it away – peeled it back – and there’s the foundation and there’s the leak; there’s the seam.
TOM: Was it …?
LESLIE: So there was no stud work behind it that pulled it away …
PETER: Yeah, there are studs; there’s stud work.
LESLIE: But was it directly upon the cement wall or was it …?
PETER: Yeah, the stud … the cement wall then the studs and then the one layer of sheetrock on my side of the office (ph).
TOM: Well, when you put the sheetrock back, don’t put sheetrock back. Don’t put regular gypsum back. Put this product called Dens Armor back. It’s a …
TOM: Yeah, D-e-n-s. It looks like drywall, but it’s covered with fiberglass. It’s made by Georgia Pacific and it doesn’t rot. So it can’t grow mold.
PETER: Yeah, because I’ve got a lot of mold down here.
TOM: Yeah, yeah. Don’t replace it with regular drywall; that’s mold food. Don’t feed the mold.
PETER: The last thing you can recommend is when I sell the house, sell it as-is. (laughing)
TOM: That’s always a strategic first step, you know? That’s like the opening bid in a poker game. Sell it as-is; you can always come back off of that, you know?
PETER: Thank you very much for the advice.
TOM: You’re welcome, Pete. Good luck with that. Thanks so much for calling us at 888-MONEY-PIT.