Proper way to lay tile backer board

[archimedes]

I'm getting ready to tile a small entry way and am reviewing different ways to apply the cement backer board to the plywood sub floor.

Supposedly the correct way to do it is to lay thin set mortar under the backer board and then screw it down.

I've set tile many times.  in many different applications and have never used thin set under the board.  I've also often used nails to hold the board down instead of screws.  I've never had a problem with any of the tile applications that I've done.  Of course I made sure the plywood subfloor was rock solid first.

It's my house and I may, some day,  want to remodel it (tastes change over time).  But  I can't imagine the job of trying to remove backer board that has been set with mastic and screws.

Mastic and screws seems like overkill.  Anyone have any input as to how you have done it. 

[rick91351]

I have laid a bunch and I thin set but it is just a skim coat and screw.  It is not like pulling a half inch notch trowel or 3/8 or 1/4.  I always used the Hardie Screws. If you have a seam even more 'over kill'.  Skim coat the seam. I use the rolls of I think fiberglass tape.  Sort of looks like screen. Most tile supplies carry it.  Lay that over the seam and follow it with a knife pulling some thin set.  I let the tape go wild and when I get to when I want it, I just set my knife vertical and give the tape a little jerk will cut it about where I need it.  (Works best if you are using an old wore-out knife that gets sharp.)   But hey if you want'a use your method and it works for you      

[Patrick]

I have always done it like Rick also,I always tape seems both walls and floors. I always use 1/2 board on floors.

[NathanS]

I did a bathroom last year and used "DITRA." Which is an orange mat with dimples in it. 1)thinset 2) ditra 3) thinset & tiles

It installed fast, I'd use it again.

[rick91351]

I did a bathroom last year and used "DITRA." Which is an orange mat with dimples in it. 1)thinset 2) ditra 3) thinset & tiles

It installed fast, I'd use it again.

Never have used that product DITRA I have seen it - thank you for the  report.  Might have to use it one of these days.  Some people up here are going to be doing a tile job this winter....   Most likely will get in on it. 

[NathanS]

I also forgot to add that it was a bathroom renovation. The old tiles were applied directly to the sub floor.. 3-4 of them popped off in 30 years of heavy use.. and that was done at new construction, so some of that could have been from the house settling..

Honestly it wasn't that bad getting the old thinset mix off the floor.. most of it came right up by using a tool that was like a nail puller only much flatter, I actually don't know what they're called. But, it was really easy to hook it right under the tiles and then hit it with a hammer to rip the tiles and thinset (or whatever they used back then) right up. After that there was some old mesh stuff that was stuck on the floor that we belt sanded off.

The demo part really wasn't bad.. the tile work itself is way more labor intensive.

[Danfish]

Key to your installation is "someday I might want to remodel"!  If removing the floor tile is in the future than backerboard installed with nails and no thin set will most likely do the job and make removal less of a task.

If you want a bomb-proof, waterproof, no crack installation...DITRA is the way to go.  Always use modified thinset to apply DITRA over plywood and unmodified to apply tile over DITRA.  I have not tried to remove a DITRA installation, but the system holds up so well I can imagine it would be very difficult!!!  One other drawback to DITRA is that it is pricey.

A DITRA install: