Bathroom Remodeling - Tiling

Hi Good Evening, finally I found a good place to get my answers

I initiated to remodel my bathroom (started with powder room). Powder room sub-floor (3/4 inch) is plywood and Underlayment(1/2 inch) was also ply wood. While removing tiles and adhesive, undelament got damaged. So, I decided to replace undelayment and successfully removed it.

Now, I am in a confused state on which approach to follow for undlayment,
Approach 1: Go with 1/2 inch plywood
Approach 2: 1/4 in plywood and on top 1/4 backer board.

I seriously want to go with baker-board approch, but since thin-set is suggested to use, I don't want to use bakerboard(1/2 inch) directly on sub-foor, since it will hard to replace again(if required to replace tiles) and I don't want to damage sub-floor.

Please provide ur suggestions for my clarifications:

• Does my approach 2 make sense and good to go.
• What type of thin-set to be used for bakerboard?
• For Approach 1, can I directly apply thin-set on plywood for tiles or do I need to use any adhesive before applying thin-set?

 

If the 3/4 plywood is solid you can use 1/4 or 1/2 cement board,. The 1/4 plywood is not going to do anything for you.

Do not use adhesives (mastic) or pre mixed mortar, a good latex fortified mortar will do fine!

 

Thanks for your response Marq1. I am not confident on my wood subfloor. I see moisture around toilet (there were some leaks when I took over), but within limits. I verified using moisture meter (

 

Usually a minimum of 1/2" ply is recommended over the 3/4, (screwed to plywood not to joists) then 1/4" cement board set in thinset.

 

I was initially planning for 1/2inch plywood over sub-floor and then 1/4inch cement board. but the floor height is getting elevated 1/4 over main floor

If I decide to tile (porcelain tile) on top of 1/2 inch plywood, do I need to apply any adhesive before applying thin-set? or just thin-set is fine

 

Usually the optimal mix is as follows.

1/2" ply + 3/4" ply (or vice versa) + thinset + 1/4" Cement Backer + thinset + tile

Use a marble threshold at the door to account for height changes. You need a beefy substructure for tile that is not in anyway beholden to the floor height in another room.

1/4" ply will do nothing for your mix and may create more issues down the road.

 

Thanks for inputs. Instead 1/4" Cement Backer , I am thinking of Ditra to compensate height issue. Would this be a better solutions?

Ditra on 1/2 Underlayment plywood
3/4" wood (sub-floor) + 1/2" ply (underlayment) + thinset + ditra + thinset + tile

??

 

Ditra might save you 1/8" at multiple times the price. Tiled quite a few floors with the mix I stated and never had an issue with height. It is only an issue in your mind.

 

Gotcha thanks for ur inputs