Learn how to lay ceramic tile on concrete. Find out why it's important to have a level concrete slab surface in order to prevent tiles from cracking.
LESLIE: Tim in New Jersey, you’ve got The Money Pit. What can we do for you today?
TIM: I’ve got a 4’x8’ concrete slab off the back of my house.
TIM: (INAUDIBLE) And it has a basement blocked off around it. And I wanted to surround the inside of this basement with ceramic tile to make it look prettier than the poured concrete that it is now and I wasn’t sure what type of mix I should use to attach this house to the block and what type of sealant I should use as far as grout  and stuff goes.
TOM: Well, you’re going to use a tile adhesive to attach, that’s for sure. You wouldn’t use a mortar mix on a wall because it’s not going to stay. So you’re going to want to use a tile adhesive. Now, the other thing is about the poured concrete walls. They may not be even enough to get a real flat tile surface there. You may want to think about using something like cultured stone instead.
TIM: Well, I’ve already gone across it with a level and flat bar and so far all the walls look pretty nice.
TOM: Nice and flat? OK, because remember tile doesn’t bend.
LESLIE: Yeah, because if you’re finding any parts where the wall is bowing out in any way, over time you’re going to get those tiles to crack or you’re just not going to get them to go on smoothly.
TIM: Oh, I found out that the hard way the first time I did a tile floor. (Tom and Leslie chuckle) I learned my lesson. I found a really nice mosaic tile they offer on the internet where they have different shapes – compasses, sea animals and stuff – glued to a brown paper bag type of material and you can apply it from the bottom of the basement with mortar mix or whatever adhesive you’re going to recommend …
TIM: … and when it dries you just wet the brown and it peels off and it leaves behind these beautiful shapes that I couldn’t possibly make on my own. And then you just grout it and it’s done and I was (INAUDIBLE) for my fountain.
LESLIE: Oh yeah, that would be really great. You want to make sure that you use a tile mastic, which is a tile adhesive made specifically for that type of tile whether it’s glass or ceramic, depending on the mosaic. Some of them even come as a mosaic/grout combo which I don’t know if you can use, especially with that fascial (ph) peeling that comes on those tiles that you’re looking at. But I would just look at the type of tile that you’re using and then just read the mastic box or the jar of it that you’re looking at at the home center to make sure it’s right for that type of tile.
TIM: When I do the grouting of the tile …
TIM: … is there a special sealant I should use after grouting the tile like I would use on my shower like a spray sealant? Or is there a special tile for this type of application with like a (INAUDIBLE)?
LESLIE: No, I think any grout sealer would work fine for this. Don’t you, Tom?
TOM: Yeah, they’re going to be – any of the silicone-based sealers would work very well, Tim.
TIM: That sounds great. I really appreciate that.
TOM: You’re welcome. Thanks so much for calling us at 888-MONEY-PIT.