Tiling a foyer

bemgolf

I am starting my first tile job and am needing some help. I have heard its all in the planning and that is the stage I am in. I was wanting to know about proper thin set. Under the carpet is osb in great shape so no concerns there. I wanted to see besides thin set under backer board is a Redgard or Ditra for a foyer really needed. Also since this is on osb and there will be movement I should probably us Modified thin set. Is this correct? Any other great beginners advice you can give would be greatly appreciated.

ps

The foyer is 12 x 5 rectangular

joecaption

No Red Guard is needed. It's only used in wet areas.
The rest sounds fine, personaly I would go over the area with a layer of 3/8 under layment rated plywood screwed down to the floor every 4" on the edges and evey 6 to 8" in the field.

Bud Cline

Could you further explain that comment? Why will there be movement?

bemgolf

I meant not on concrete.

Bud Cline

Shouldn't be any undo movement.

You can use either cement board (1/4"-1/2") in thinset or DITRA (1/8"-5/16") in thinset.

Which underlayment you choose could determine which thinset to use.