Wetroom 3 different ways?

[Jon329]

Hello everyone,

I tried to avoid asking this question as I'm sure you're all sick of seeing the same questions being asked, but after days of research I am unable to choose the best flooring to put down for a small ground floor wetroom on a suspended timber floor. 1.65x1.85m room dimensions

So I have taken up all the water damaged chipboard and want to replace it with something of a similar height to avoid having a step going into the bathroom. I have bought a 22mm tuff former from screwfix, so I also need to match that height

From what I've seen from various forum are these are the suggestions.

1) 18mm ply wood then 6mm aquapannel (tile board) giving me a 24mm height floor. But unsure how prop up the former by 2mm or if it's close enough.

2) 25mm ply wood floor, then get 3.6mm ply and place that under the tuff former to try and level it.

3) I've seen some 22mm tongue and groove plywood from travis perkins. "Selex Structural Plywood B/C Grade Tongue and Grooved 2425mm x 600mm x 22mm" on the manufacturers website it says this is actually 21mm height but I'm thinking I could put some uncoupling membrane on top to get it level with the tuff former.

I'm thinking option 3 might be the best. But I know that some people say 25mm ply is the minimum for laying tiles?

Any advise would be greatly appreciated!!

 

[Chalker]

Hi
Personally wouldn’t have used the screwfix former, there are better ones about. But as you have, as Long as you suppor it well, it will be fine.
I take it you have a void under your joists? If so , make sure you insulate it while you have the floor up. If there is any deflection in the floor, you will need to install noggings between the joists ( 400mm Centers, or 18inch if you have imperial sized ply.
Don’t worry about the 2mm height difference, as long as your using decent sized tiles, you can overcome that with adhesive. Other than that you idea of floor build up is fine. Use plenty of screws and glue the ply to the joists. I would have used 6mm insulation boards. They are easier to cut.

The main thing with a wet room is waterproofing it. Personally, I would used Ardex this uses a fibreglass tape applied to any joins and corners. Then cover the floor and walls, which will be getting wet.

 

[Jon329]

Thank you for your help, could I ask what type of insulation you would use? I hadn't intended to use any underfloor heating and hadn't even considered insulation. I'm guessing foam insulation like celotex?

 

[Jon329]

Bump

 

[hmtiling]

Thank you for your help, could I ask what type of insulation you would use? I hadn't intended to use any underfloor heating and hadn't even considered insulation. I'm guessing foam insulation like celotex?

marmox , wedi type boards. they're cement coated xps

 

[Waluigi]

@Jon329

18mm ply and overboarded with 6mm Hardiebacker or similar. Glued, screwed, taped and filled.

I would concentrate on getting this right in your head and think about the height this gives you.

Your wet room former can easily be raised slightly to reach the same level as the rest of the floor. Simply board out in between joists slightly higher.

I’d get the wet room former in first but have some offcuts of Ply and Hardiebacker to hand as your reference point.

As you have no UFH going in, I wouldn’t consider an Insuition board personally. That’s not to say that there is anything wrong with using it.

 

[Jon329]

Thank you all for your time and advice. It's all coming together, just need to get some sort of tanking kit now, any recommendations?. The shower area is actually surrounded by solid walls luckily, but it seems people still advise tanking them. Only other questions I have is that you have mentioned glueing the plywood down, any glue in particular? Guess just normal wood adhesive?

 

[Waluigi]

Paint on membranes I’d use either Tilemaster or Ardex. Membranes on a roll, I find Schlüter Kerdi a good choice but there are lots available and all do a similar job.

The ply isn’t glued, it’s the Hardiebacker that is glued and screwed, on top of the ply, using Tile adhesive.

 

[Jon329]

I guess because it's a very small room if I were to buy the paint on membrane then i could do the shower walls and floor all with the same stuff and it looks cheaper! however the membranes on a roll does look more "fool proof"

Might just have to be brave and go for the paint on!

Has anyone used the akw membrane though, don't know if it's best to use the manufacturers own membrane to go over my akw tuff former

 

[Jon329]

Trying to fit the waste for my former, can anyone advise where I can get the part I need or
What it's called? I'm just trying to connect a 50mm pipe to this 50mm adapter on the soil pipe, but all I can find are reducers?! I can push a 50mm pipe connector on the end but I don't think there's sufficient depth on the outlet to be correct. I'm just trying to mirror what's been done already to the other 50mm outlet.

I'm right in assuming this will be solvent weld I hope?

 

[J Sid]

one of the Plumbers on this Tilers Forum maybe able to help

 

[Waluigi]

It will be solvent weld or at least it should be. Certainly the end that joins to your stack will be, the other end might be ring seal.

The fitting you require is called a ‘Boss Adaptor’

Being honest, for wetrooms I’d go for 50mm solvent weld waste right up as close to the wet room drain as possible.

With boss adaptors they are manufacture specific so you need to find the brand of ‘boss coupling’ that you have to know which boss adaptor you require.

I can’t think for the life of me which brand of fitting that is you have. Worse case scenario replace the Boss coupling. Simple job really.

 

[Jon329]

Thanks waluigi, yeah I'm trying to maintain the 50mm pipe as my shower waste is also 50mm and want it to drain faster. It's all very much like patch work unfortunately, however I can see that the air vent says "marley"

Just out of interest, why is it important to match the brand, I'd of thought they were standard sizes? In this case its exactly the same dimensions as the 50mm solvent weld waste pipe I've bought, so probably 53mm

 

[Waluigi]

Hmmm not quite as simple now you’ve panned out

If you can try to measure the diameter of the boss and then perhaps try a merchants. Both Screwfix and Toolstation are out because they tend to have the awful rubber boss adaptors and won’t go up to 50mm.

Selco uses Hunter plastics. Osma might fit. It’s very much trial and error unless any of the other Plumbers here has an idea? Sometimes a 50mm solvent weld pipe will glue straight in.

 

[Jon329]

Okay thanks for the advise, as I said the 50mm connectors do fit but i don't know if it's a good enough join as it soil pipe connector is so small it will only go half way in

 

[Waluigi]

Sorry I missed that....

Absolutely fine gluing direct to the boss adaptor imho

 

[Jon329]

Ideal, thanks. Was just worried as the person who originally did it seemed to go to alot of effort to not do that.

 

[Jon329]

I have seen this though

 

[Waluigi]

Does that 45 degree bend push in all the way?

 

[Waluigi]

That osma fitting might fit, it might not. It’s pot luck

 

[Jon329]

No only pushes in about half way because the boss adapter isn't long enough. Picture probably explains it better

 

[Waluigi]

That’s fine, I was just looking at the pic before and it looked like it could go further.

It’s no different to gluing a Boss adaptor in.

Provided it’s not really loose, by the time the weld has melted in, it’ll be a solid joint. Keep in mind that it takes a good amount of time to fully set.

 

[Boggs]

You can glue fittings direct to a Marley boss, you can get 2” fittings that have a smaller female end with boss written on them.

Like this


Just don’t forget to drill it out.

 

[Waluigi]

, good point. Never forget to explain the obvious

Can you just imagine that on a new wet room

 

[Boggs]

I’m only speaking from experience

The bath and basin held the air test brilliantly

 

[Jon329]

Hahaha give me a little credit! I haven't seen the smaller end ones before, I was actually going to use my mitre saw to cut a bit off to get the same result, but I'll keep my eye out for some of them!

Thank you both, got a plan now! shame I never actually managed to get anything done on my only day off! But all clued up for next week

 

[Bond]

Also worth abrading the fittings with sandpaper prior to gluing.