Remove and Replace porcelain floor tile.

We are planning to replace the floor tile in our master bath. Just an aesthetic upgrade, no structural issues. The original tile was installed professionally back when the house was built in 1998 so I assume (hope) they followed standard protocol with plywood, mortar, cement backer, mortar, tile. I looked at a transition area and it's hard to tell. I can see the plywood but cannot distinguish between the mortar and cement backer. I guess my question is, how much do I have to remove? Is it possible to just remove the tile and top layer of mortar or do I have to go all the way down to the plywood? TIA

 

Really depends on how well adhered things are. You may frustrate yourself with trying to remove all the trowel marks. It takes a lot of patience But can be done. 3" stiff putty knife used as a chisel and cut across the trowel lines. You also need to watch if it is destroying the backer board. If they used Durock or Permabase, it is concrete with mesh embedded in it. If you destroy the mesh, you may weaken the floor. Hardibacker tends to delaminate and may come up in chunks still stuck to the tile. Won't know until you get there.

 

Thanks czizzi. I'm going to start this tomorrow so we'll see what I run into. In your opinion, would a reciprocating saw with a scraper blade be of use?

 

Never had one, so I don't know. I have chipped a whole bathroom and tub surround before so I know what you are in for. Happy experimenting!

 

What do they say? Never assume anything. It looks like they just put down 1/2" plywood, then mortar (or thinset, don't know the difference) and then tile. What are my options?

 

Get the existing tile out and we can plot the next moves once you know for sure. That said, if there's only 1/2" of plywood, you're going to have to add some layers.

 

most of the tile is already pulled up. the subfloor is 1" OSB. the tile was installed on 1/2" screwed down plywood with a thin bed of mortar. The joists are 16" OC. And the span is 15'.

 

Remeasure the OSB as 3/4" is more common. 1" is more indicative of a wet environment when the house was being built, Excessive rain may have caused the OSB to swell. Take a drill and make a series of holes in the field of the subfloor. Take a 16d nail and put it down the hole and pull back up such that the head captures the bottom of the subfloor. Pinch the nail at the floor height and pull out. Measure the thickness of the floor.

 

You are correct. Actually the OSB is stamped as 23/32" nominal, so yes, 3/4" plus the 1/2" plywood.

 

I find an SDS drill with a flat blade does a good job of loosening the tile and grout.

 

I tried the chipping suggestion but was not getting anywhere in a hurry on the nearly 100 sq ft bathroom. I found a youtube video demonstrating use of a 7 " grinder with a diamond cup wheel so rented one locally and finished the job in a few hours. The rental did not come with a dust shroud so I spent more time cleaning up after myself than actually grinding so would highly recommend getting the shroud.