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02-26-2008, 03:17 PM
Going to attempt my first tiling project this weekend. I think I have a pretty straight forward project but PLEASE tell me if I'm on the wrong track.

I will be tiling a 5' x 5' bathroom floor in the basement. The concrete is about 15 years old, no cracks, not smooth-smooth but not real rough either. It's flat with a slight slope (about 1/4" in 5') never been sealed water does soak into it.

Planning on buying 12"x12" ceramic tile, trowel with 1/4" x 1/4" x 3/8", tile cutter (not a wet saw), and nippers. Thinking of 1/4" gaps and grouting with Polyblend sanded grout.

Should I use RedGard?

Leveling compound?

MegaFlex or Flexbond?

From what I read the thinset can last up to 4 hours in the bucket after it's mixed. So I should be good with one 50lb bag and thinking of working an area of 4 tiles at a time.

Please shout out any recommendations! Since it's such a small job, I don't mind spending a little extra for products if they're worth it.

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02-26-2008, 06:09 PM
level isn't a big thing as much as being flat, you really need a flat floor.

you can use Redgard or FractureFree from Custom
or look into installing some Schluter - Ditra (

02-27-2008, 08:45 AM
"Should I use RedGuard"...

Yes, if you have a water permeation issue no if you are in the Gobi desert...OK a facetious answer but using Redguard brings up the issue of efflorescence and, since we don't know where you are located and whether or not your basement has high humidity levels, or water tables permeating your floor, we can't really say with certainty. At least, I won't...

If it were my job, the first thng I'd do is test your floor for water permeation. Then depending on the results of that, I'd cautiously say "We're good to go" with your plan, perhaps using a decoupling membrane.

From reading your post, I don't see a major issue with the floor not being "true".(PS: I make a distinction between "flat" and "true"; 'flat technically = "level". I don't need "level", I need "true". True may be level but not always. 'True' is a bit like 'straight')

But if the floor is pronounced dry, I would also make provisions for sealing the grout. If you wash the floor regularly, you'll thank me :) in about a year's time. Or swear at me :tongue: if you don't.

02-27-2008, 12:49 PM
Floor has always been dry no water issues at all. Humidity levels are low as well (SW PA), especially in the basement. I wouldn't hesitate on the RedGard if the price was cheaper. I would only need a little bit and I only saw it in one size for about $40. They guy at the home improvement store said no one uses that stuff. That's why I wanted to run it by some experts.

As far as the flat vs. level thing. Using a 4' level on the floor, there are no gaps underneath the level but the whole floor is slopping about a 1/4" over the 5' span in one direction. Wasn't sure how critical that was.

Anyone have any thoughts on which thinset I should consider?


02-27-2008, 01:56 PM
Not an expert but I just put down 12x12 tile the other night with 1/4" grout lines on a concrete basement floor. I used Versabond latex-modified thinset based on the advice of this forum - you can get it at Home Depot.

I had a concern with how the versabond would adhere since the floor was troweled smooth. I called the manufacturer who said as long as it is not shiny smooth or sealed it should not be a problem. I did a test with a small bit of thinset elsewhere in the basement. I couldn't get it up after it dried so figured it would be good for the tile. :)