Newly plastered bathroom and tiling.

[wrightyintheafternoon]

I'm refurbing my bathroom and fitting a quadrant shower tray. One wall will be MR plasterboard to hide the pipes and the other is newly skimmed plaster. I was going to prime the plaster side with SBR with something like this https://www.toppstiles.co.uk/tprod8763/bal-bond-sbr-primer-1ltr.html, does the MR plasterboard need priming as well.

The tiles I have are 500x250 and concerned about the weight on the new skimmed plaster. The shower tray is 900x900 so will have about 17 tiles on each wall if my calcs are right plus adhesive and grout. Not concerned about the MR board sustaining the weight just any thoughts about the new skimmed wall and tiling on to it. I've read that the skim should also be left for a number of weeks before tiling which if so will be a PITA.

 

[lostinthelight]

Did you consider tanking?

 

[wrightyintheafternoon]

Did you consider tanking?

Yes that's an option although when discussing the installation with my plumber he said not always necessary. Would that improve the wall strength as well.

 

[Paul C.]

Yes that's an option although when discussing the installation with my plumber he said not always necessary. Would that improve the wall strength as well.

Sorry, your plumber is wrong. All showers now need tanking for the work to conform to British Standards. Without it, you'll invalidate the warranties for all your tiling materials. Only needs a quick coating of the Ardex WPC in the wet areas, which is about £60-£70. Cheaper than risking your plaster or plasterboard getting soaked, mouldy, turning to mush and the tiles falling off and having to redo it.

Also, it won't make it stronger, the tanking with match the substrate weight limit which is 20kgs per sqm on the skim. In hindsight, you would have been better off not skimming (Plasterboard holds 32kg's). But if your tiles are ceramic, they will be within the limit for plaster skim.

 

[wrightyintheafternoon]

Sorry, your plumber is wrong. All showers now need tanking for the work to conform to British Standards. Without it, you'll invalidate the warranties for all your tiling materials. Only needs a quick coating of the Ardex WPC in the wet areas, which is about £60-£70. Cheaper than risking your plaster or plasterboard getting soaked, mouldy, turning to mush and the tiles falling off and having to redo it.

Also, it won't make it stronger, the tanking with match the substrate weight limit which is 20kgs per sqm on the skim. In hindsight, you would have been better off not skimming (Plasterboard holds 32kg's). But if your tiles are ceramic, they will be within the limit for plaster skim.

Hi Thanks for that, The tiles are 500x250x7mm ceramic. https://www.tilechoice.co.uk/51-5x25-7-sydney-gris.html.

Also the shower enclosure will be against the outer edge of the larger tiles and the cuts into the corner will go behind the tiles off the false wall so will assist in supporting the weight if that makes a difference. Its only a 900mm quad shower tray so just less than 2 tiles wide and 5 tiles high give or take.