Water Leak Through Basement Wall Crack: How to Stop
LESLIE: Next up, Chris in Utah with a crack in the basement. What’s going on?
CHRIS: Well, I’ve got a crack in the basement wall. The area I’m in has a very high water table. We do have a sump pump installed. However, if the sump pump fails for any reason, the water starts leaking through the basement wall, causing a fair amount of flooding damage. This happens on a fairly regular basis. So I was wondering if there’s any way that we can seal the concrete in some way so that we don’t have a problem with flooding anymore.
LESLIE: Chris, are you from Australia?
CHRIS: I am indeed. (laughter)
LESLIE: I love that accent. “Aw, yee-ah, Chris has got a crack in the basement wall.” (laughter) Alright, Chris, so tell us; is it vertical, horizontal, is it deep? Tell us about the crack.
CHRIS: There are also little cracks in the floor and the water comes up through that as well. The crack kind of runs horizontal then slopes down towards the floor.
TOM: Chris, does it seem to leak more after a heavy rainfall?
CHRIS: It’s out towards a bird refuge and it’s a wetlands area. So, whenever there’s heavy runoff during the spring, the water table comes up and that’s when the water pressure from the water table starts forcing it in through.
TOM: What I would recommend here is a multi-step approach, Chris. First of all, we want to take every step possible to reduce the volume of water that’s getting close to that foundation wall. So I want you to look outside your house first at the gutter system to make sure that you’re collecting as much water as you can off that roof, that all of the gutters are free flowing and that the downspouts are discharging away from the foundation at least – at least four to six feet. The next thing I want you to look at is your grading. The angle of the soil around the house has got to drop away four inches to six inches over four feet. If it’s flat, the water’s going to stay right against the foundation. Also, look at the kind of dirt that you have around. If you happen to have a lot of mulch, if you have any kind of a landscaping edge that’s holding water against the foundation, that can trap water as well and that’s a problem.
So we want to manage the water around the outside of the house so that we have less water that gets against that wall, has the opportunity to sort of push through the wall or push under the wall coming (audio gap) the floor. Because it sounds to me like what’s happening is very consistent with this spring runoff and it may not totally be a high water table issue that you’re seeing. Even though water’s pushing up through the basement floor, that could happen when water kind of works its way around the outside wall and has no place else to go.
Now, in terms of that crack, you certainly should seal the crack. And by the way, that crack is probably the direct result of the water that’s collecting around the outside wall, freezing in the winter time and pushing on the wall. And that sort of ratcheting effect can move the wall a little bit every winter and that could be a big problem because eventually it might get so big that the wall could become unstable. So another good reason to manage the water on the outside of the house.
In terms of the crack on the inside, you want to caulk it with a paintable caulk and then you’re going to want to damp-proof the walls. But that’s the last thing you should do. The first thing you should do is really address the drainage issues outside. Because what we have found is that in most cases, you can keep a lot of that water away from the walls and this other problem inside just goes away on its own. So even though you think it’s high water table, I want you to look at the grading and the drainage first. And I think that’s probably the best way to handle this situation.
Chris, thanks so much for calling us at 888-MONEY-PIT. 888-666-3974.