Question for you tile experts?

[07Custom]

Hey guys, I'm remodeling the upstairs bathroom in my house and have some questions regarding the flooring. Previously there was some awesome teracotta tile in there, but it was cracked. I started chipping it away and it seems that the installer simply used mortar on top of the OSB subfloor, which sucked. It was fused with the wood and left dips in the subfloor.

I'm smoothing it out with some feather light mortar. I bought some hardiboard (1/2") in hopes that it would provide a smoother surface to bond the new tile to. I had read that I needed to reinforce the flooring with plywood, then use hardibacker then set the tiles. This would definitely raise my floors too much.

I have elected to just use the hardibacker and am having some internal debate on how to fasten it to the OSB subfloor. The salesman and a contractor friend of mine expressed that I can use liquid nails and screws and it would be just fine. Online forums and the hardibacker website recommend using thin set mortar. I keep reading positives from both sides. I already bought the subfloor liquidnails but am a little unsure of it due to the previous tiles cracking.

I hear that the mortar isn't necessarily to fasten the hardibacker down, but to provide a way to fill in the air pockets and gaps of uneven floors...which I have.

So...should I be okay with hardibacker, liquid nails, and screws...or am I setting myself up for more issues?

Thanks much guys!

 

[Kyle]

mortar route. ive used liquid nails before and its alright if your doing some quick job but if you want it done right. go with mortar. just my 2 cents.

 

[DJinCO]

How hard would it be to tear out the OSB and replace with proper plywood and hardibacker board? The rest seems like a band-aid fix.

Then you would not have the sub-floor higher than you want.