Leveling a Kitchen Floor
LESLIE: Alright. Don in Indiana has a question about a sagging floor. What can we do for you?
DON: Well, I’ve got a kitchen floor that’s sagging in the middle.
DON: And …
LESLIE: What is your flooring, already?
DON: Well, it’s got just stick on tile. And I’ve got a basement under it.
TOM: So it’s a wood floor.
TOM: And is the basement ceiling finished, or not?
DON: Yes, it’s all finished.
TOM: Ah. Okay. Well, that makes it complicated.
DON: Is there something that you can put on there to level that floor up before I put some kind of subfloor on there or something? Because I’d like to put some regular tile on there.
TOM: Some ceramic tile?
LESLIE: Well, if it’s sagging, does that mean that perhaps that there’s a joist issue and the subfloor is being … is being forced to sag because the joist isn’t supporting it? Or do you think there’s something with the integrity of just the subfloor?
TOM: Well, if the …
DON: Well, the house is about 35 years old, 40 years old. And it’s not sagging in the basement – that you can see.
DON: You know. So …
TOM: I’ll tell you what it probably is. It’s probably a sag or a reverse crowned floor joist. The first thing you need to determine is whether or not the floor is really sagging like in a big way or, perhaps, the floor joist next to that is higher than the one that seems to be sagging. Because you could also have a crowned floor. Sometimes, when you have one floor joist that’s high, one floor joist that’s crowned the other way – no, it’s curved; every beam is slightly curved and it’s called crowned. And in a perfect world …
LESLIE: Right. But, generally, you’re supposed to make them all crown the same way.
TOM: Exactly. The framer’s are supposed to crown each board and put it pointed up but they don’t often do that. However, I think the solution, here, is going to be in the kind of floor you want to put in. You said you want to put a tile floor in. Well, I don’t know what you think, Leslie, but I think if he put a mud floor in he could straighten out all these problems.
LESLIE: Well, yeah, the mud floor will provide a …
LESLIE: … level and stable structure as your subfloor.
TOM: Yeah, and you just use a little bit more mud in the areas that are … that are … seem to be sagging. And it’ll give you additional structure and it’ll look great. The only tricky part about this, Don, is … you mentioned it’s in the kitchen. You have to really watch the appliances – especially the dishwasher – because a mud floor is pretty thick. You’re going to probably need at least three-quarters of an inch to an inch of floor there. And so, what you might need to do is pull the dishwasher out while this is being done …
LESLIE: Any appliances that are sort of built in or trapped into a space – like the dishwasher – where it could become wedged in if you do raise that floor up.
TOM: Otherwise, you’ll not be able to get it out. You follow us?
DON: Right. Is this mud floor … what kind of mud are you talking?
TOM: Well, it’s a lightweight concrete floor. It’s a standard way … it’s the way they always used to put tile down before we started putting it on top of plywood. It’s basically a cement floor.
LESLIE: Would you use like a Quikrete? Like one of those?
TOM: Yeah, it’s a … well, it’s a special … it’s a special mud that the tile … tiles guys use it. It has a nice viscosity to it so it can be leveled and troweled in place. And you put that down first – becomes a perfectly flat surface – and then you tile right on top of it.
When you talk to the tile contractor, Don, just tell him that you’re interested in a mud job. They typically call that a mud job. And they’ll respect you as a man of quality (chuckling) because that’s the best way to do it, anyway.