Tiling onto plaster for shower/bath

[CambDIY]

Hello,

I’m doing a DIY bathroom job and would be very grateful for some advice.

The bathroom is in a 2nd floor flat in a converted Victorian house. The bathroom walls for the corner into which the bathtub and shower will sit appear to be dry walls with wool insulation, foil backed plasterboard with thick plaster on top set around wire mesh.

There was an existing bathtub but no shower. We’d like one so I have chased into the plaster to make space for copper pipes (please see picture). I had been planning to wrap the pipes in duct tape, secure in place with a piece of wood (temporarily), whilst filling in the chased holes around the pipes with cement and then plaster before re-tiling the back wall. I’m aware of the general weight limit of 20kg/m2.

However, I’m now concerned re the possibility of water damage from the shower if the walls have not been properly tanked. Is this something I should worry about or would you expect the area to be water tight once tiled and sealant applied to the corner areas?

I suspect the existing tiling would have been “splash proof” but perhaps not shower proof.

I have considered stripping both walls right back to the plasterboard, screwing on tile backer board and priming, taping, etc., which I’d rather avoid but will do if people think it’s necessary.

Or any other suggestions would be appreciated.

Thanks!

 

[SimonG]

Screwfix do a Mapei tanking kit. Paint on a couple of coats prior to Tiling.

 

[Knappers]

I like the paint-on tanking, use leftovers for sink and hob cutouts

 

[Knappers]

It depends what you want to do and what the budget is.
You'll probably be ok with plasterboard and good cover of waterproof adhesive if you make sure tray is well sealed to wall and again after tiling. Of your replacing boards then use green ones.
Next step would be paint-on like the mapei with rubber seal strip which I like (don't try laping strip over tray but rather fit flat on wall and seal tray to it).
Then you've got options with cement boards and full membranes which I'd consider if using a porous tile or mosaics with lots of grout and a must for wetrooms.

 

[ShaunCorbs]

Make sure them stubs for the shower are long enough

 

[CambDIY]

Make sure them stubs for the shower are long enough

Thanks all - very helpful

 

[king of pipes]

You have two choices either use the mapei tanking kit as below , or use 6mm foam cement faced tile backer boards the area needs making good priming before fitting in boards and screwing back to the wall every 300 mm with s/s washers

 

[William Norman]

isn't is within building regs now that all tiled wet areas in a bathroom. ive seen a video on Skill Builder https://www.youtube.com/user/skillbuilderchannel that explains the new rules

 

[Ric2013]

isn't is within building regs now that all tiled wet areas in a bathroom. ive seen a video on Skill Builder https://www.youtube.com/user/skillbuilderchannel that explains the new rules

Your first sentence contains a typo so not sure what you mean. The link would be helpful, but all it does is link to the channel. What's the name of the video in question please?

 

[exedon2]

Think you may be referring to new regs on tiling from N H B C. that came in this year.
Building regs on tiling changed in 2018 (BS 5385-1)
Main change was to exclude plywood as a tile back board.

 

[king of pipes]

Tiling methods and materials have progressed greatly over the last 10 years, same old story though with change comes extra cost and there will always be tradesmen who cut corners building regs don't even get a second thought. Kop

 

[hometech]

Think you may be referring to new regs on tiling from N H B C. that came in this year.
Building regs on tiling changed in 2018 (BS 5385-1)
Main change was to exclude plywood as a tile back board.

NHBC are an insurance company LOL, they have no statutory authority. Just like the regulation a(1)a from WRAS which headline in red at the top of the regulations

For the reasons above, WRAS accepts no liability for loss of goodwill, business, revenue or profits,
anticipated savings or wasted expenditure (whether reasonably foreseeable or not) or indirect or
consequential loss arising from or in connection with this guidance document.

 

[WC1]

I have tiles on marine ply done more than 15 years ago by my dad in a let flat. Still going strong today.

 

[William Norman]

Your first sentence contains a typo so not sure what you mean. The link would be helpful, but all it does is link to the channel. What's the name of the video in question please?

Sorry here are the videos i was on about

 

[Ric2013]

Hmm. We're talking about British Standards. Does the relevant building regulation make specific reference to the British Standard. If not, I'm not sure we can talk about it being 'outlawed' as the video presenter puts it.

I'm getting rather cynical these days. Seems to me we're pushing higher standards to force people to use certain proprietary products and I wonder whose interest we're really working in.