Upstairs floor / shower

[EkPosh]

Hello All,

First post, so not sure if in correct forum, but hope you can help.

I am installing a shower tray in the upstairs bathroom. Basically, there is no floor. So what I have is joists, and at right angles to that (to lift the floor up) I have wood battens. (like a frame I guess)

Am I OK screwing 25mm WBP ply directly onto those? Then putting some sort of cement / sand mix to lay the shower tray? I am just wondering whether this is strong enough?

I was also thinking of thermal aquapanel. Would this go on top on the ply or could I use that instead of ply?

Thanks!

 

[Blagard]

Am I right in thinking your battens are to raise the base of the shower tray above the bathroom floor level? That is not a bad idea if you would have a problem accessing the waste trap from below.

25mm WBP ply would be more than adequate as a base to your shower providing it is supported at normal joist centres. Make sure the Ply is fitted level, don't assume your joists/ battens are!

Is the Shower tray, Fireclay? If so, I would only consider a sand cement bed if it gave the slightest hint of a wobble on the ply to indicate the tray underside was not truely flat.

Pay careful attention to the wall finsh/ shower tray joint. If you do it properly you should not need to worry about the ply below. Same goes for the shower waste fitting.

 

[EkPosh]

That's correct - its to raise the floor level for better access to the waste. If truth be told, we have just bought the house and the previous owner built this shower but tiles over loads of small squares of ply which were on the joists. It was a balls up and needless to say, we had water in the kitchen.

How much gap would I have to have between the frame? ie battens at 20cm intervals or is more like 40 suficcient?

Not decided on a shower tray yet, probably stone resin or something like that.

I am planning on tiling the walls after installing the tray so will leave on overhang, so Im hoping no leakage at all!

Thanks

 

[Blagard]

How much gap would I have to have between the frame? ie battens at 20cm intervals or is more like 40 suficcient?

Around 40cm would be fine. Get your tray first so you don't end up putting a batten under where the waste needs to exit! It also gives you a chance to adjust so you can get at the trap when its fitted.

I always use screws to fix timbers in my own home. It does not cost that much more and is cleaner to undo your work if not quite right!

My bathroom WC had a slight wobble when I positioned it on my wooden floorboards. I bedded it down on some P38 plastic padding (Car panel repair filler). 20 Years on it is still solid.

I would expect a Resin Shower Tray to be true. Whilst you would naturally follow the manufacturers recommendations for fixing (if any), If none, I would probably screw some small locating battens onto the ply to ensure it could not slide when placed in final position (they would abut the inside sides of the tray so not visible when tray placed over them)

Be prepared to chop away some wall plaster to ensure the top edge of the tray can get under where your tiles or wall panelling are going to be. (plan ahead)

 

[EkPosh]

Thanks again.

As the whole floor is raised (only small area - maybe 1200 x 700mm), would I also have to run battens in the line with the joists?

At the moment, my battens are at right angles to my joists. If I then cover this with 25mm ply, I would rather put the ply at right angles to the joists (so in line with the battens). Should I also install battens in line with the joists (on top of them)? And of so, what is the best way to attach the battens to the joists?

Thanks!

 

[Blagard]

As the whole floor is raised (only small area - maybe 1200 x 700mm), would I also have to run battens in the line with the joists?

What size are the "battens" you have fitted so far?
I was thinking this was a local area in your bathroom raised for the shower only. Or is this some sort of en suite shower in a 1200 x 700 space?

So long as your battens are substancial, say at least 2" x 2", you could fit them either way, across or along the joists. Your choice really would be guided by the waste pipe you will be fitting below the shower. Further battens should not be necessary with the ply you are using

Fixings options will depend on the height of the batten. The simplest being like a spacer along the top of a joist screwed down from the top. All you are trying to do is to pin them to the joists. Once ply is fitted to the battens the whole lot should be pretty solid

 

[ajrobb]

Just a thought - fitting battens on top of joists gives you the chance to have them as furring strips of variable thickness to ensure the floor is both level and flat.