Wetroom with UFH - preparation and tanking

[AliGage]

I got confused on a post recently where Ash (Mr TeaBag) asked some questions over tanking with a spread on gum waterproofing.

I'm in the middle of a wetroom install at the moment so thought I'd share my pictures.

This job was originally prep'd by someone else, consequently very poorly. So, SLC, UFH, durabase, puddles of adhesive, offcuts of OSB, and rotten floorboards were all removed to reveal rotten joists.

Joists were repaired, support for new wet tray created, some plumbing altered and 18mm WBP marine ply screwed to new timbers.

Marmox boards installed. Glued and screwed with washers.
UFH cable and probe installed.

I used some off cuts of marmox boards to make a "flood barrier" for the SLC. Once set they are removed and the wet tray gets covered and shaped for falls.

Then it was on to the tanking. For this install I used BALs WP1 and Orby jointing tape and corner profiles.

Once dry we can start our tiling!

 

[Mr Tiler]

whhoooo tiling yehhh! lol what exactly was that I was asking about ali? not sure what ya ean there I lioe these posts with plenty of insightful pics brilliant mate.

 

[AliGage]

It was the illusive tanking video post with the exciting German drinking cans of NOS

 

[Mr Tiler]

oh haha yeh lol still stand by the fact that those vids are very informative although get a little boring!lol

 

[CJ]

Nice to see a small rubi. Thought I was the only one who has the star cutter.

 

[AliGage]

Always a handy, compact cutter for little ceramic jobs.

 

[Chalker]

Lots of prep there. Great job.
as for the cutter I've got one in th garage that I don't use. ( no wheel) free to anyone that's pm's me wyh their address!

Its got your name on it Ash

 

[Mr Tiler]

haha! site scavenger here mate il have it lol 😛arty:

 

[Chalker]

haha! site scavenger here mate il have it lol 😛arty:

going , going , gone.
to Ash the skip rat!

 

[Qwerty]

Great post Ali, cheers

Ash, I have some used spacers you can have if you like? 😉

 

[Martyn Leeds]

I've never done Metro's in a bathroom yet, but I can tell that that's gonna look the shizzle when done..

Keep the pics coming on this one

 

[STEVO]

Ali, when you say "tray gets covered and shaped for falls" , have you made your own falling tray in there? Or have you added some form of screed/addy in there following the falls in order to bring the edges upto rest of floor height?

 

[AliGage]

The later mate. But the floor was quite out of level as it ran toward the door. So in an attempt to bring it right the wet area became quite deep. Yep there is a marmox former in the bottom. But when covering the cables the nearside was built up 20mm where as the back corner was less than half that.

I used a thicker mix of fibre reinforced SLC and effectively rendered the wet area following the falls in the former. If that makes sense?

 

[STEVO]

yep, gotcha. thought thats what you were getting at.

 

[AliGage]

Here's some updates on progress:

 

[Qwerty]

Very nice Ali 🙂

 

[SteveyJ]

HI, Great work, floor prep looks awesome. Can I ask a quick question, I know you stated you used 18mm WPB to put straight on the floor joists, any reason why you didn't use 25mm, or is 18mm more than sufficient for tiling onto without flex? I'm not trying to be a smart arse or pick you up at all I just wondered. Also when you said about the SLC what type do you use? I have always mixed up some rapid set flex and flat troweled it over, but would much rather use a level compound (without the need to fall level over the tray!!!). Cheers

 

[AliGage]

HI, Great work, floor prep looks awesome. Can I ask a quick question, I know you stated you used 18mm WPB to put straight on the floor joists, any reason why you didn't use 25mm, or is 18mm more than sufficient for tiling onto without flex? I'm not trying to be a smart arse or pick you up at all I just wondered. Also when you said about the SLC what type do you use? I have always mixed up some rapid set flex and flat troweled it over, but would much rather use a level compound (without the need to fall level over the tray!!!). Cheers

Evening Steve,
Floorboards were 18mm so used 18mm ply to marry up with the boards at the threshold of the doorway. 18mm is sufficient as long as you put noggins in for additional strength/support.
6mm indulation boards were then glued and screwed over the top.
Once UFH was laid out I used Mapei rennovation screed to cover.

 

[SteveyJ]

Hey Allister, Thanks appreciate that, obviously you have done it before so not had any issues with movement. I will bear that in mind next time I come across a similar situation.
Also never used any Mapei product before guess its the same as BAL fibrebase? Guess it sticks to the marmox fleecey tape stuff ok. What sort of mix do you do over the Marmox tray to stop it levelling out, mix it up like adhesive, quite stiff? Is there a ratio you use? Cheers Steve

 

[AliGage]

Yes mixed quite "stiff" no set ratio. Loose enough to float around but stiff enough to stay put. Have to keep working with it over 30-40 minutes. Once it stays put and your happy smooth it over with a damp sponge.