Stop Basement Flooding With Proper Drainage
LESLIE: Billy in Pennsylvania has a question about how to fix a concrete floor. So Billy, my question is what’s wrong with it?
BILLY: I have an old farmhouse and the basement floor ended up being not concrete but it’s like a limestone covering.
BILLY: It’s real thin. We had a big flooding problem so we had one of those basement systems put in. That’s how I found out about what kind of floor we had. So I had to put some sort of vapor barrier down and then I want to cover the floor. I was wondering what to cover it with. I was going to do concrete but everybody’s saying that you need like four inch … four inches of concrete. And then, that would take away a lot of head room.
TOM: Yeah. Now, right now you don’t have … you no longer have a water problem down there?
BILLY: No, it … when we … when we get flooded, it … that pumps going 24/7 almost.
TOM: Right. Did you get the flood or do you get the flood consistent with heavy rainfall; like when it rains a lot around your house?
BILLY: Yeah, the water table comes up into the basement.
TOM: That’s not water table. That’s a drainage problem outside. Because water tables don’t move that quickly. I just want to encourage you to look at the grading and drainage issues outside your house because your pumps are probably running more than they have to. When you get moisture consistent with precipitation – be it snow melt or heavy rainfall … so look outside your house at the grading, the angle of the soil around the house and the gutter system to make sure it’s clean, free-flowing, that all that water’s being diverted well away from the house. And I do mean like four to six feet away from the house. That’s going to reduce the volume of moisture because even though you’ve got these pumps, what happens is you get a lot of water that forms outside the foundation wall. Then in the winter time, Billy, what happens is that freezes and it pushes on the wall. And over years, it has a ratcheting effect and can actually cause those walls to crack.
Now, in terms of the floor – yeah, if you’re going to put concrete down, you do need to put a good four inches in there. If you’re not going to do that or if you’re concerned about head room, you’re going to have to dig out what’s there to make room for the concrete. The surface that you have right now, being very, very thin, is just not structurally sound enough to be able to support any kind of finished surface. So if it’s going to have a utility purpose for you, you might have to take that out, go down, you know, two or three inches to get enough of a surface to put down some woven wire mesh and some concrete to be able to give you net the same head room that you have. But I wouldn’t put anything on top of that because, if you do, it’s just … you’re just going to have a deteriorated base underneath.