Shower Install Advice - Tanking???

[adrian bond]

Hi Guys,


This is my first post so please be gentle! I will be as brief as I can


Basically I am creating 2 x new showers in a house (it’s a new student let house). One is a 800 x 800 corner unit, the other is a 1000 x 760 rectangular built in unit.

Both new bathrooms have been created using Gyproc moisture resistant plasterboard (green) that has been dot and dabbed (this is fine from the manufacturer, I checked first) on some walls onto the existing awful walls, or screwed to tanalised CLS timber depending upon which bathroom and wall etc.


On one of the 760 walls which create the rectangular shower, this is fresh plaster skim over the old wall surface in standard thistle multi finish, which then butts up against the moisture panel of the remaining sides of the shower enclosure. Hopefully you can visualise them!


I have built up the shower bases from 18 & 22mm waterproof ply, and raised them on tanalised timber to get the correct fall in the stone resin shower trays (the riser kits were cheap plastic legs!!!). I have also bought 2 x sets of aqua straps http://aquastrap.com/ to create a waterproof lip which can be tiled upon when the time is right. The tiles I’ve chosen are the standard Metro white tiles available from everywhere (B and Q, Topps, Wickes etc). Waterproof tiles with a glossy front and about 200 x 100 rectangular and pretty lightweight at 7mm thick (no overloading of the boards).


From reading some of the threads on here, I now understand that moisture resistant plasterboard isn’t quite man enough to be used as a shower enclosure un tanked as it will still leak and fail! Therefor I have decided to invest in this kit here for each shower; http://www.screwfix.com/p/mapei-shower-waterproofing-kit/78484#product_additional_details_container


1. Now first question is do I fit the shower trays down using flexible cement with the aqua strap Silicon to the walls first or do I tank the walls first?


2. Second question is regarding adhesive. In my haste (and before discovering this forum) I have purchased BAL grip plus adhesive (15kg) BAL Grip Plus | Tiling Products | BAL Adhesives and some micromax2 Micromax2 | BAL Adhesives grout from tops tiles. I still have the receipt so can take it back if required…..but is this stuff okay to use on tanked walls and will it give me the water proofing I require in my showers? Or should I take it back and get something more suitable?


3. Any tips is should be aware of before I begin as this is my first foray into tiling and fitting showers (I’m doing it all myself where possible to learn and to try to save some costs if possible).


Thank you for all your replies guys. They really are appreciated.

Adrian

 

[On one]

If it is a student let.....the first thing I would do would be to take the tiles back and get something bigger.
In that scenario with a tile that small and so much grout it is going to become filth dirty very quickly.

 

[Dan]

If you tank the walls before tiling, and after fitting the shower trays, you tank actually to the shower tray so the wall becomes one with the tray. So you won't really need those strip things.

Finish off with a bead of Silicon then and you're done and water tight.

Adhesive wise, your tiles aren't heavy so it should be fine.

I'll leave the structure down to the lads.

 

[adrian bond]

thanks for the replies guys. ive bought a grey grout (micromax2) which should hide the dirt in the showers as best as possible. i think we can all agree that the students wont be cleaning the shower after each use! (big humidity extractors going in each room).

is the adhesive (Bal grip plus) suitable for this install and will it help to keep the place watertight! i really don't want to have to replaster the kitchen ceiling again if there is a major leak!

 

[Flintstone]

Persoanlly I would tank the wall down to the floor, then fit the tray and Silicon it. Zero chance of the plasterboard seing water then. Tile with a flexible powdered adhesive.

 

[Dan]

The adhesive isn't there to waterproof it, that's the job of the tanking kit.

So you rest a tile on the shower tray and draw a line in pencil on the tray, so the line is a tile thickness away from the wall.

Then you tank the wall and the tray up to that line, so 10mm onto the tray, or whatever. Use the internal corner tanking tape onto the tray and in the internal corners.

Then even without tiles, that's completely water tight.

 

[adrian bond]

this is brilliant guys thank you. if i still want to use the aquastraps as a double reinforcement; i take it i fit those to the tray and then the assembly to the wall after the wall has been tanked?

i read on another post somewhere that some people have done the first layer of tanking, then fitted the trays with the aquastrap, then tanked over the top of the aquastrap with the tape and sealing solution.

does that sound like madness or genius? (i have already bought the straps and they werent cheap....i kinda want to use them!)

 

[Dan]

It's something else that can go wrong then. And the guarantees and things from the adhesives and tanking might be void, you'd need to speak to the adhesive manufacturers and take it from there.