Learn how to avoid water seeping into your basement. Find out how creating good drainage outside your home and cleaning out gutters will keep your basement dry when it rains.
LESLIE: It’s been a stormy summer in the U.S. and Ken in Delaware is having a leaky basement  when it rains. How can we help you?
KEN: What I have is I wanted to locate a toilet roughly 20 feet away from the drain that runs out to the street in my basement. So what I did is with a jackhammer, I broke a – dug a trench basically; busted up the concrete floor from that drain that runs out to the street over to where the toilet’s going to be installed. So having busted through the concrete floor, I then put a pipe in and it had the proper slope to it and everything. So the toilet function works perfect. The problem comes in when I filled in the trench with new, fresh concrete, I poured the concrete in; leveled it all out  and it looks nice. However, when it rains, the hydrostatic pressure from underneath the floor comes up and it seeps through between the interface between the new concrete that I poured and the old concrete which I busted up with the jackhammer.
TOM: Yeah, you know why? Because you created a nice trench for that water to find it’s way right back into your house.
LESLIE: To pool up in, too.
TOM: Yeah. It’s like when you have a hole in a foundation wall and sometimes people will call and say, “Well, this hole always leaks when it rains.” Well, it’s not the hole that’s leaking; it’s just where the water happens to find the path of least resistance. But the solution to this, Ken, is the same.
LESLIE: Yeah, Ken, you want to look at the outside of the house because this is where the water is finding its way into your basement . So you want to look at a couple of things. Make sure the grading is good. You want to make sure you’re going down about six inches over four feet. So it’s not really that much of a drastic slope but it’s enough to slope that water away from the foundation. And then, also look at your gutters and your drainage system. Make sure your gutters are clean  because if they’re dirty or they’re overflowing, they’re going to backsplash up and over the gutter and get under your roof and behind the walls and that – even though it’s on the wall or upstairs in the attic – can find its way all the way around down to the foundation and end up in your basement.
And look at your downspouts also. You want to make sure they deposit the water about six to 10 feet away from the house. Get it the heck away from the house. And also, make sure those downspouts are clean because if a stick or something is stuck in there, that could cause things to back up as well. So if you do all of that, you should be able to control that moisture in the basement .
KEN: What I was wondering is there any kind of a seal that I could paint or plaster over top of the concrete to kind of keep that from leaking up because it’s clearly coming right in between the fresh concrete that I poured and the new concrete that was already there that …
TOM: Ken, does this floor leak consistent with the heavy rainfall? Does it seem to leak when you get heavy rain?
TOM: Well, if it’s leaking when you get heavy rain, you’ve got a drainage problem outside. And anything you put on to try to seal that at this point, it may not be effective. You’ve got to figure out where the grading and the drainage design of the foundation perimeter of your home is going bad. Because if your basement leaks consistent with rainfall, it is always, always, always due to a problem with the grading or a problem with the gutters.
TOM: And once you fix that, the water’s going to go away. So, go outside. That’s where you need to look and that’s where you’re going to find the solution to this problem. And after you solve it, then and only then could you look at something, for example, like an epoxy floor paint, which works well in the basement. QUIKRETE  makes a good one, for example, that’s effective. But that’s not going to stop a leak if you have that water ponding on the outside of the house. So that’s what you need to do first and the painting’s what you need to do second; or any other type of sealant. Make sense to you, Ken?
KEN: OK, I got you. OK, I’ll give that a try.
TOM: Thanks so much for calling us at 1-888-MONEY-PIT.