i'm getting ready to install ceramic tile in my basement and just finished the chapter in my home depot book about what's involved with this. it said i should be using backer board to keep the tiles from flexing. as i say, this is going in my basement, which has a concrete foundation. aside from making sure the floor is totally level, do i really need to use backer board?
tks
Probably not. I did my whole den with 12X12 ceramic tiles on concrete slab and it came out great. Any minor imperfections are usually taken care of by the thinset. As long as the floor is level you'll be OK.
thanks mike. how long ago did you do this?
>No backer board and floor doesn't need to be level. It just needs to be flat.
Now, if you have a painted concrete floor you will need to get off the paint. The most recent TOH magazene suggested backer board over a painted concrete floor. Personally I would prefer to sandblast or strip off paint than install backer.
So no, do not need backer.
Back in October. So far it's rock solid.
If this is an old slab that has no cracks you will be OK. In new construction they usually use a membrane under the tile to isolate any cracks that occur.
I also did 12x12 ceramic tile in my kitchen and bathroom on a concrete slab 7 years ago. There has been no problem with it at all. My only suggestion is don't use white grout. It's very hard to keep clean even with sealer.
Backerboards are not designed to be installed over concrete slabs. Like "No" said, level's not critical,. An even or flat floor is.
How did the article suggest the backerboard be attached to the slab?
There's no reason in the world to add backerboard over a concrete slab. Anti-fracture membrane of sorts? Yes. But not backerboard. Did that Bob Villa asswipe suggest that?
Painted slab should be etched with muriatic and a modified thinset used for setting the tile.
Check the requirements from the self-leveler mfg'er. Why do you feel you need the leveler? Have you laid a straight edge of some sort across the floor?
i was talking to somebody at Rona over the weekend and she suggested that i could put a coat of regular latex primer down on top of the painted slab and this would be sufficient for priming the foundation for a layer of self leveling concrete. does this sound right?
the leveler i bought was EZ Flow. each bag is $30.00 CDN which is going to get really expensive as i've got a lot of area to cover (about 350 sq ft.). i asked why it was so expensive and she said it's because it's self leveling, as though there were some high technology to this. i'm trying to keep the costs down on this project so wanted to get some feedback from the group on alternative and cheaper ways to do this before dumping more money on the EZ Flow primer.
the floor itself has some pretty nasty high spots on it where it looks like the foundation buckled in on itself, so i've got to bring the level of the entire room up to match this. i'm considering just using regular concrete and trowling as best i can to get a level floor, but suspect i'll still have some high/low spots. after getting the floor as level as i can, i'll add another layer with the self leveling stuff to get what i miss.
i don't mind the extra work it takes to get the floor level by using non self leveling stuff, but i'm not sure i've got the skill level to trowel the room level. a straight edge is only going to measure about 1 metre across at a time, but what if the room is 6 metres across? how do i level the room without a 6 foot meter or does it not matter?
tks
Allthouhg I've never used that one IIRC, anyway the EZ part of using floor levelers isn't always 'easy'. Damn near perfect consistency is necesssary for it to flow yet not too wet as to weaken it. Yep, not cheap either. I use them seldom and often times use a traditional mortar bed.
Regular concrete? Nope. Needs aggregate (rock) to be concrete. And mortar (sand/cement) doesn't hold well when feathered thin as you would need to do at the high spots. Perhaps you could look into pre-floating a 1"+ mortar bed throughout, or having one done for you.
Straight piece of wood? Remember 'level' is good but not always possible so 'even and flat' are the important issues. You may want to just grind down the high spots.
Use a straight 8' - 2x4, overlapping sections.
overlapping sections. yes, of course. tks.
Thinking about it, you could lay down something to maintain a constant height in areas that are already level. I'm thinking of something like aluminum "L"s laid so that the "V" is up. You could then use the top of the "V" as a base for the screed. Doing that in sections that are already good then using those sections as the height for the bumpy sections should get you a pretty good floor even if you used your one meter straight edge as the screed..
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We used that all the time. It's call "Level Cure" here. The thing to use when trying to keep a low elevation. Make sure you purchase the primer (bonding agent) when pouring directly over concrete.
Also make sure you chalk the boards to the floor that will divide the rooms. The stuff is like water when it hits the floor. Use a roll of paper towels for any leaks to plug. ;o)
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