[kiteman]

I have some unscheduled time off, it's cold, and it's supposed to snow, so I'm about to tackle redoing my master bath shower.

Just a little background. When we bought this house 18 years ago it had a really bad 4' shower in it. At the time, my wife always took baths, whirlpools were the thing, so I wanted to put a jacuzzi in. I took out a 6" furred wall on the right and "borrowed" 6" out of the walk-in closet to accommodate it. Now I want to take it back to a 54" shower, returning the 6" back to the closet

My plan is to use a Kerdi tray and Kerdi board on the walls with a 12" seat on the right side. No curb, but possibly the ramp. We've picked out a Mohawk Bertolino Nocino Travertine porcelain tile in 12"X24" for the bath floor with the matching polished ceramic for the walls in the same size, with the 3" mosaic for the shower floor.

I went to the contractors' supply house today and I can get all the Kerdi supplies at contractor pricing, so that's a big help.

Any advice will be appreciated and don't be afraid to tell me I'm nuts. I've gleaned a lot of info from you guys here.

Thanks in advance.

Dean

 

[the rock]

Dean,were all NUTS....I could be misunderstanding,but why return 6" back to the closet?Sounds like to much rough in work to gain just 6"in a closet.Other then that it sounds like you have a solid plan.I would do Ditra over CBU on the floor.Good luck with your project.Nick

 

[JazMan]

You do not install Ditra over CBU, one or the other.

Tell us how the framing and subfloor is built, including species and grade of the joists if possible.

Jaz

 

[Tech Dawg]

If anything, add minimum 5/8th plywood for strength, membrane and then tile...

Whatever you decide, please do it soon because that bathroom is horrendous :laughing: :thumbup:

 

[kiteman]

It's 5/8 plywood decking over 2x10 SPF fj. It's over a 2' interior cantilever that creates the hutch space below, so the bearing wall is almost directly under the center from side to side.

 

[Tech Dawg]

I'd put 3/4 ply over the existing subfloor.

 

[JazMan]

OK, 5/8" is very cheap a** of the builder. The fact of 2 x 10" joists means nothing without the span.

Need the whole thing. Please add the spacing of the joists and the span to the inch. The grade would be helpful too.

Jaz

 

[kiteman]

Ok, 2x10 #2 or better, 16" oc, total joist length 16' 4", with a 2' cantilever at either end, so clear span between bearing is 11' 8". The span tables for here say that grade and spacing is good to 15' 5".

I agree that the 5/8" was cheap, but it was the standard here in 1981.

 

[kiteman]

I'd put 3/4 ply over the existing subfloor.

So when you do that, what consideration are you giving to a transition to existing carpet?

 

[JazMan]

kiteman,

You're correct that;

The span tables for here say that grade and spacing is good to 15' 5".

But, you're not considering the correct type of flooring. That spec, (40lb/10lb live/dead load), is good enough for vinyl or carpeting, It's not so good for ceramic tiles. I recommend you use 50/20. :thumbsup:

So, if these are regular SPF (not south), you meet minimum at about 13' 0". That of course is if they're installed correctly and still in perfect condition.

So. you gonna add another layer of underlayment? What type of tile backer will you use?

Jaz

 

[Tech Dawg]

So when you do that, what consideration are you giving to a transition to existing carpet?

You'll still have to measure up your deflection calculations. 5/8 subfloor is a cheap move on the builder so pending your calculator, I'd use 3/4 ply and a thin membrane like Nobleseal ts.

At the doorway, you can use a single hollywood bevel strip, or have one fabbed at a local shop if your floor height is el-wacko

 

[kiteman]

I'm planning on the Kerdi preformed tray for the shower base. So you are both saying that the 5/8" subfloor with Ditra is not sufficient, even though that meets the minimum requirement in the Ditra hand book?

What if I left the existing 1/4" underpayment where the vinyl is? It's in very good shape.

 

[kiteman]

You'll still have to measure up your deflection calculations. 5/8 subfloor is a cheap move on the builder so pending your calculator, I'd use 3/4 ply and a thin membrane like Nobleseal ts. At the doorway, you can use a single hollywood bevel strip, or have one fabbed at a local shop if your floor height is el-wacko

I was going to carry the tile through the door along the vanity, since this has the rather unorthodox feature of carpet there.

So then I have a transition from the carpet to the tile that I can do with carpet shims if I don't go over an inch in height.

 

[VinylHanger]

I can already see where this is going. You are going to stay on here for three days asking lots of questions. Then when you are finally ready, it will warm up and you will get back to work in the real world and tell your wife it will have to wait. Three years from now it will start all over.

At least that's how it works in my world. I have a new bath fan that has been sitting in the garage for 2 years now. :laughing: I still have a few questions about it. :whistling

 

[kiteman]

My wife won't let me get away with it now that I pulled the tub today. Finishing up putting her closet back together after I move the wall back might be a different story.

It has actually made it up to +2 degrees now.

 

[Tech Dawg]

I'm planning on the Kerdi preformed tray for the shower base. So you are both saying that the 5/8" subfloor with Ditra is not sufficient, even though that meets the minimum requirement in the Ditra hand book?

What if I left the existing 1/4" underpayment where the vinyl is? It's in very good shape.

Moisture from the thinset will delaminate the luan.

 

[kiteman]

Moisture from the thinset will delaminate the luan.

Excuse me for being dumb, but are you referring to just the 1/4" and not the decking? Why does it delaminate one and not the other?

 

[kiteman]

Btw, it's wafer board ul, if that makes a difference.

 

[JazMan]

5/8 t&g plywood as a subfloor does meet minimum specs in home building, but it scares us to install a quality floor over it. Schluter also says 5/8" ply exp. 1 subfloor grade is ok, but it still needs to meet L360 deflection specs. Do you know if it does? How you gonna check?

It's best to install an underlayment grade ply over to stiffen it up a bit. The thinnest you can consider is 3/8". But I recommend min 1/2" preferably thicker. The more the better. So the 1/4" stuff you have belongs at the curb.

Todd thought your underlayment was luan since it used to be a common product to use under vinyl. Yes, luan will delaminate fast if it gets damp. You never ever tile over luan.......ever.

Jaz

 

[kiteman]

I hadn't planned on keeping the wb anyway, so I will add a layer, under the Kerdi tray as well.

These are just the kind of issues I want to resolve as I go. Thanks.

Next question. I would like to build the bench first ( out of 2" Kerdi board) and butt the tray up to that. That a problem? There's some plumbing to cover up that way. Not a big deal either way for me.