Wetroom - is my shopping list right?!

[TheForge]

Hi Guys,

I appreciate that this is "yet another" newbie question, so I'll try to be clear and concise!

I'm sourcing the materials for an ensuite with wetroom style walk in shower.

Drawing here:


Current state here: (right of photo is the shower area, photo taken from the "office" into the ensuite, bedroom in background.


From my research, this is what I need for the wetroom shower area/rest of the floor:

1. Shower wet-deck/former. I'm looking at the AKW Level Best/Tuff Form, as it seems the strongest/requires no underbaording/is suitable for mosaics.
2. Tanking Liquid/Membrane. I'm considering the Lastogum kit which is liquid based (with corners/tape etc) but wonder if a sheet membrane/decoupler is better? like the BSA Membrane kit
3. Tile backer boards for the area around the actual shower, (eg: hardiebacker). We're having to chip the (200 year) old plaster/render back the stonework anyway, as it's falling apart, so makes sense to go for cement based waterproof tile board for the walls...
4. Floor.. taken the old floorboards up (200 years old and beautiful, will reuse elsewhere in the house). My builder has put chipboard down as a temp measure. What should we go with? Marine ply with Tile backer board over? Or just the current chipboard with Tile backer board? We'll have mosaics throughout the floor/shower.
5. Considering electric ufh.., if so, I believe this just fits over the tile backer board, with latex screed over the top.

Anything else I've missed?



Any comments/advice/experiences/suggestions are very much appreciated. I couldn't put in links to the products I've mentioned as I'm a new user, but will try to add later if I can.

:2thumbsup:Cheers!:2thumbsup:

James

 

[TheForge]

OK, after another day of research, am thinking of Durabase wp for the shower area walls, and durabase ci for the floors. Seems I'll still need tile backer/marmox board for the walls and floors?

Or is this overkill?

 

[AliGage]

No such think as overkill for a wetroom in my opinion. The more groundwork you do now the better.

 

[TheForge]

Agreed, I don't want to be ripping this out to redo it!

I'm still a bit unclear on the buildup of the layers...

Floor, From the top down:

---------------------
Mosaic Tiles
Latex screed
durabase ci
electric ufh
cement board/tile backer board/marmox
chipboard floor
---------------------

is this right?

Obviously in the actual shower area where the former tray is- no latex levelling layer and no UFH.

 

[Qwerty]

All seems good apart from I didn't see what type (material) tiles you are fixing.

Marmox or similar is perfect over the top of a new ply floor with UFH on top. SLC over this.

Marmox on the walls too if heavy tiles being fitted as opposed to a tanking gum.

Hope this helps!

 

[TheForge]

Hi blocko,

Thanks, feel like I'm gaining clarity!

All seems good apart from I didn't see what type (material) tiles you are fixing.

Small (40x40mm, fairly thin) glass mosaic tiles to the entire floor, plus will use these on the walls of the shower area too. Elsewhere (less exposed to water) the walls will most likely have a larger ceramic tile.

Marmox or similar is perfect over the top of a new ply floor with UFH on top. SLC over this.

So, do you think that the dura ci membrane isn't needed? Or would that go ON TOP of the SLC? (with just the mosaics on top of the membrane?

Thanks!

 

[Qwerty]

Wow! Glass mosaic on the floor! Quite ambitious. Yes I would personally be fixing down a decoupling membrane in this scenario but I'm not overly convinced at all that a glass mosaic floor in a wetroom is advisable, especially thin glass. Make sure you establish which type of glass mosaic backing you have as you may require a different adhesive.

 

[TheForge]

Ambitious from a technical perspective? The tiles were chosen in a tiles shop (for floor) use, so I wasn't aware this was anything unusual (although I appreciate the warning!). I did look at using durabase ci, but after reading their instructions, it seems they don't advise it with 40x40mm mosaics.

They are glass, but they've very small.... so to my mind, they take little load (per tile) as the weight of your (for example) foot is spread over numerous tiles.

 

[White Room]

50 x 50mm is the smallest due to point pressure

 

[TheForge]

So, can 40x40mm mosaics be used on the floor, or is it a big no-no? Currently, the layers would be:

Mosaics
adhesive
membrane (not entire floor)
adhesive
SLC
Elec UFH
adhesive
tilebacker board
chipboard floor


Thanks

James.

 

[Qwerty]

James, I would say no I'm afraid. Point loading on the former could cause serious issues.

Also, the adhesive needs to be between the backer boards & substrate. And please, please don't use chipboard. Get some WBP ply (min 18mm) instead. Apologies I didn't pick up on that yesterday, only just realised you mentioned chipboard

 

[Impey Showers]

We'd love to see the glass mosaic finished result.

 

[SJPurdy]

You can use mosaics on the floor but not over the decoupling membrane or the insulation board.
I'd suggest from the top down:

mosaic
adhesive (good quality cement based mosaic fix)
SLC (good quality and stated as suitable for over UTH)
UTH
6mm "no more ply" (or similar) tile backer board glued and screwed (and primed/sealed)
18mm exterior grade ply (sealed on back and side edges) and screw fixed at 300 c/c max. (extra noggins may be required)