New to this forum, but have been looking at the good suggestions for some time.

I am looking to install ceramic tile to existing 2nd floor bathroom. Removed existing floor down to 2 x 6, 3/4" planks. Secured loose or squeaky planks.

I am planning on installing 1/2" plywood on top of planks and 1/4" backer board for the 1/4" tiles. Everything I have been reading says to use thinset for the backerboard.

Toilet flange is 1-1/4" above plank subfloor so these measurements would seem to add up ok, I hope.

This is a small bathroom measuring 60" x 104"

Joists are 16" on center.

Am I ok on this plan?

Also, if you use thinset to install the backerboard and have the plywood screwed into planks.......how would you ever remove the floor in the future if the screws are covered with the thinset, or is something I should even be concerned with.

Thanks for the help/ advise in advance.

Murph

 

I'd be very concerned with just 2 X 6's for floor joist.
How long a span are they?

 

I think I'd suggest a minimum of 5/8" ply if the planks are fairly rough. And I would not worry about removing the screws someday. If you think it will be YOU, make sure all your screws are in nice straight lines and put a band of 1" wide masking tape over them. I would never do it but someone might thank you. In reality, I can't see anyone ever taking up the subfloor for any reason.

 

no, the 2 x 6 planks are on top of double 2 x 4 joists

 

attached is a pic of the subfloor

 

Let's back up. You said they were 3/4" planks and they grew to 2x6. And your floor joists were 2x6 and shrunk to doubled 2x4's. May help us if you posted pictures of joists and subflooring.

Edit. That was fast. I don't think those are 2x6s on the angle. 2x4s are never used for subfloring, so we need clarification

 

OK I must plead ignorance here, as I thought the joists were the structural boards that the planks sit on. the planks are 3/4" x 6", my bad there(not sure what I was thinking)

If I look between the 3/4" x 6's(or basically 1 x 6's)there are double 2 x 4, or maybe they are 2 x 6's as I am only going on what I can see between the plank slats. not sure if it easy to see the joists, looking between the plank gap, in the attached pic.

 

Does that make more sense?

The joists are not 2 x 4', but either 2 x 6 or 2 x 8's.

 

Stick a coat hanger down through one of the cracks until it either hits the ceiling of the floor below or you can "hook" the bottom of the joist and measure how thick it is. We already have one vote for 5/8" - I recommend 3/4" Advantech (or equivalent) then 1/4" cbu then tile which should add up to your 1 1/4". Take the time now to screw down all the 1/6 planks to prevent squeaks.

Don't worry about removing screws down the road, if done correctly, the floor should outlast both of us.

 

Thanks everyone. Yep , measured and joists are at least 2 x 8, but maybe even 2 x 10.

I will take the advise here and go with 5/8" ply

Thanks again and sorry for adding to any confusion.