To tank or not

[PhooBear]

What are the tiles and size?

Mosaic 30 x 30 two strips
60 x 30 gray porcelain tile

 

[Old Mod]

60 x 30 gray porcelain tile

Yeah if they’re 7 mm thick and above, they’re technically too heavy for plaster I’m afraid.
Porcelain is approx 2.4kg per mm per metre.
Plaster has a weight limit of approx 20kgm2
Plasterboard 32kgm2
With adhesive, 7mm porcelain is approx 21kgm2
If you total peace of mind and longevity, you should consider plasterboard in dry areas and wedi style cement board in wet areas. (Not cament board like Hardiebacker) wedi style is waterproof, Hardie is not, it still needs to be tanked.
In a perfect world you would have wedi style boards all round.
Or maybe even a waterproof render if it’s to brick work.
I realise it’s very late in the day, but you did ask in time.
Tough choices to make now.

 

[Tile Fix Direct]

3-Fall's comments make a lot of sense. We supply Orbry waterproof backer board that could be used in the tiled areas instead of plasterboard. Plaster as a substrate for tiling is not suitable for tiles over 7mm, or less if you apply a wet waterproof coating to the plaster.

Orbry Waterproof Insulated Tile Backer Board (1200mm x 600mm)

Shop Orbry Tile Backer Boards from Tile Fix. Find Orbry products in our huge range of cement boards and tiling supplies. Free delivery on orders over £375ex.

www.tilefixdirect.com

 

[PhooBear]

Yeah if they’re 7 mm thick and above, they’re technically too heavy for plaster I’m afraid.
Porcelain is approx 2.4kg per mm per metre.
Plaster has a weight limit of approx 20kgm2
Plasterboard 32kgm2
With adhesive, 7mm porcelain is approx 21kgm2
If you total peace of mind and longevity, you should consider plasterboard in dry areas and wedi style cement board in wet areas. (Not cament board like Hardiebacker) wedi style is waterproof, Hardie is not, it still needs to be tanked.
In a perfect world you would have wedi style boards all round.
Or maybe even a waterproof render if it’s to brick work.
I realise it’s very late in the day, but you did ask in time.
Tough choices to make now.

Thank you for the info, if Wedi board is used in the shower area, it does not need to be tanked? If the walls are uneven or holed wld u just put up the boards and the tile on top this is definitely a minefield for me, thanks for taking the time to answer my questions and hopefully give me price of mind.

 

[Old Mod]

if Wedi board is used in the shower area, it does not need to be tanked?

Only board joints, transitions and mechanical fixings need to be tanked.
If you are using actual Wedi you can glue edges with their 610 adhesive which is waterproof.
Then only mechanical fixings need to be done.
There are other boards available that do the same job, it’s just that wedi boards are easily searchable, so that you can see what type of board they are.
They do happen to be top end tho.
You can straighten walls with the boards.
Take manufacturer recommendations on what adhesives to use.
You can dan the back of the board with adhesive and using larger or less amounts erect the boards plumb. When adhesive is dry, use mechanical fixings thro the dabs. (Mark their position when sticking to wall) there are required numbers of dabs per sheet, again take manufacturers advice.
You should end up with something like this.

Sorry have Probs with images, I’ll try sort it.
[automerge]1570616879[/automerge]

 

[PhooBear]

All noted thanks for the info

 

[Unused Account 1]

Always telling builders ,clients ,dont plaster the tiled areas once boarded,especilally with big format tiles,waist of money and more weight onto plaster board

 

[PhooBear]

Always telling builders ,clients ,dont plaster the tiled areas once boarded,especilally with big format tiles,waist of money and more weight onto plaster board

Plasterer cancelled, bathroom now back to brick at the moment

 

[Dumbo]

Plasterer cancelled, bathroom now back to brick at the moment

Nice, insulation boards fixed as @3_fall said . Proper job

 

[Wetroom specialist]

Hi

I am having my bathroom refitted with shower tray and glass screen, bath taken out and all tiles removed, plasterer coming to plaster full bathroom. Guy doing the bathroom work states tanking not neccessary when the walls have been plasterered, you only need to tank when tiles are going on walls and floor, and he also did not price for tanking and this would involve extra costs, would rather be out of pocket now rather than later. My son says the shower area should be water proofed.

Just worried if tanking is not done and I then have problem further down the line, all advice would be greatly appreciated.

Bottom line is that this is NOT a wet room. Sure you can tank the walls as best practice. But a true wet room does not have a shower tray, it has a floor former. This is then tanked and at least a meter past the wet area (more commonly the whole floor). By using a shower tray you will be relying on 50 pence worth of Silicon to stop it leaking. My bet is that the fitter has suggested a tray as it is quicker to install. A wetroom will cost a bit more. But if you fit good products from one brand you will not only be waterproof but in many cases have a lifetime guarantee.