New tile project

[SilverBullet07]

I have a new tile project my wife gave me. She wants our front entrance foyer redone. I’ll be using ditra for a non coupling membrane. The tile is 12x24 porcelain. I’ll use Versabond thinset under the ditra. Can I use Versabond LTF under the tile or do I have to find a un modified thin set to use?

[cx]

What is the subfloor, Harold?

[SilverBullet07]

It’s two layers of plywood. Either 3/4 and 1/2 or two 5/8. There is ceramic tile down now that I have to take off. But everywhere there has been tile they had two layers of plywood. Under that is trusses..

[cx]

Little more specific, Horold.

These are the same 2x4 assembled 24" trussed with 24" spacing as in your previous project?

Guessing at the subflooring may be fun, but I don't recommend it.

Your previous tile was bonded directly to the top layer of plywood?

[SilverBullet07]

Yes same trusses and all the tile laid by the previous owner has been laid directly to the plywood. I’ve been taking the old tile up and grinding down the thin set. So far I’ve been getting the plywood clean. Then I thin set the ditra to it. I just can’t remember what the ply thickness was but it has all meet the standard when I researched it. I’ll know more when I remove the tiles. I just want to make sure I get the right thin set to lay the tile on the ditra.

I think ditra recommends unmodified to lay tile on ditra ansi 118.1 but I thought most say the Versabond 118.4 is fine on top of ditra. I can get the Versabond LFT easy and wanted to make sure I could use it.

[cx]

If you're at all interested in the Ditra manufacturer's warranty, you'll need to find a good un-modified thinset mortar. Otherwise, the VersaBond should work just fine. I've never done any testing with the LHT version of VersaBond, but I know the regular VersaBond will cure just fine in that application. We generally recommend following the product manufacturers' installation instructions, so it's entirely up to you what you use.

My opinion; worth price charged.

[Metropolitan Ceramics]

As CX said, the Versabond will likely work but if there are any warranty issues, you will be out of luck. Schluter makes their own mortars now which allow you to use a modified mortar and still get the warranty. May want to give them a call first.

[SilverBullet07]

Thank you. Would the custom blend non-modified thin set be ok to use with 12x24 porcelain tile? Or do I need some sort of LTF thinset?

I ran across this MAPEI Uncoupling Membrane 50-lb Gray Thinset/Medium Bed Tile Mortar. It says it is for Can be used for large format tile and stone (15-in and greater) when used with an uncoupling membrane

Should I just use the Mapei?

[Lazarus]

Do NOT use the cheap Customblend unless you mix it with their liquid modifier at about $30 for a jug. I would just go with the Versabond LFT...

Mapai makes a good, unmodified morter (Kerabond) if you can access it.

[SilverBullet07]

How is MAPEI Uncoupling Membrane 50-lb Gray Thinset/Medium Bed Tile Mortar. I see that at my local store.

[cx]

I would not recommend either the Custom or the MAPEI "uncoupling membrane" mortars. That is, of course:

My opinion; worth price charged.

[ss3964spd]

If Mapei is what you have available to you Ultraflex 1 or 2 should do the trick. Both meet ANSI A118.11 for adhering to plywood. You can use it for setting your porcelain tile (many manufacturers recommend a modified thinset mortar for porcelain tile) directly on plywood (though not recommended here) or to adhere Ditra to the plywood, and then tile to the Ditra.

If you have Custom Building Products thinset mortar available (Depot is the usual source) their Versabond will also work, as will Flexbond. Though you don't technically need it both come in a LFT version.

[SilverBullet07]

Our local tile store has ditraset and Schluter set. Either of these recommended to set 12x24 porcelain tile on ditra?

[cx]

Not familiar with Schluter Set, but the DitraSet will work fine.

My opinion; worth price charged.

[SilverBullet07]

CX
I finally got the tile removed and the thin set cleaned off the plywood. You were asking what the sub floor is. I have 2 sheets of plywood. First layer a 1/2 inch and a 3/4 in plywood under it. Then the 2x4 assembled 24" trussed with 24" spacing.

I will lay ditra un top of the 1/2 plywood using custom Versabond modified then laying the porcelain tile 12x24 using the ditra set un modified.

Hopefully I’m good to start laying the ditra.