Help!: Porcelain tiles onto green plasterboard.?

[Gazebo]

Hi all,
Hopefully this will be easy to advise, i have dark grey 600x300 porcelain wall and floor tiles to be fitted to....
1. 18mm overboarded Ply floor fixed every 300mm

2.Stud walls lined with 12mm marmox construction board and green moisture resistant plasterboard.

I am confused as to what needs priming prior to tiling, i have read many of the posts and threads with ref to this but still in a muddle. I am obviously going to use a Spf addy and a fast set Spf for the floor, and a flexi coloured grout(mapei probably) but do i need to prime/bond the cement board or only the plasterboard, and what about the ply floor.?
Tiles are apparently pre sealed (HTW sourced) any other tips would be appreciated, will post photos of job when complete, give you all something to laff at.

Cheers, and be lucky.
Gary

[grumpygrouter]

Only the plasterboard will need priming. The ply should have been sealed on the back and edges with BAL Bond SBR before laying (assuming you are use BAL products of course).

Big tiles will require a big notch trowel, even for the wall, and if it was me, I might consider using rapidset for the walls too, as the tiles are heavy and rapid set will get a "grip" quicker. If you are not very experienced standard set my be a bit easier though for the walls, as you have indicated.

[365drills]

Agree with Grumpy. But in my house we went for belts and braces and used a BAL tanking kit to cover EVERYTHING. Plus we used the taped joints to make sure everything was water tight from ceiling to floor.

Overkill and the Bal kit was something like £100 to do it including the fibreglass tapes. The main reason we went so mad is because of the variety of materials in use to incldude plasterboard, ply, soft wood batons 2x4, brick, plaster etc etc.

The tanking kit for me was a £100 security blanket to prevent long term leaks. 5yrs later and all is well.



A mix of plasterboard, ply and softwood = Bal tanking kit



We didnt install a shower tray instead creating a fall with tiles. Hence even more of a reason to make sure the area was water tight.



Tested !

[Oli]

Richard, did you round of the corners of the walls as a feature or to cover pipes, it looks great.

[365drills]

Hi the corner has a 4" soil stack from the loo upstairs and so rather than box it in leaving a sharp edge in the way of the body jets I softened up the corner with an angle.

it was either that or move everything forward by 4" to leave a flat surface. But then you would have less shower space / floor area.

It seems to work and leaves a bigger footprint.

[whitebeam]

If you are laying big tiles with spf on the walls don't go to high until the lower ones have set, The spacers can be a bugger to pull out with all that weight

[Gazebo]

If you are laying big tiles with spf on the walls don't go to high until the lower ones have set, The spacers can be a bugger to pull out with all that weight

Thats a good tip whitebeam many thanks.

[Gazebo]

Hi 365,
many thanks for the quick response, nice shower by the way, how do you create the base for the shower floor, did you use wet room formed tray or.???????
i have submitted some pics of my own, feedback would be appreiciated as long as its constructive. hehe.....be nice in other words..

[grumpygrouter]

If you are laying big tiles with spf on the walls don't go to high until the lower ones have set, The spacers can be a bugger to pull out with all that weight

This is exactly the reason I try and use rapid setting stuff now. By the time you have got a couple of courses up, the bottom courses have set enough to remove any spacers without further slippage.

[madmark hatter]

hi gg, do you mean use BAL bond SRB on the back of the plywood facing the wall as well as the edges?

[grumpygrouter]

hi gg, do you mean use BAL bond SRB on the back of the plywood facing the wall as well as the edges?

I thought the ply was on the floor?

[Gazebo]

woot woot yes it is on the floor

[Dave]

If you are laying big tiles with spf on the walls don't go to high until the lower ones have set, The spacers can be a bugger to pull out with all that weight

Leave the spacers in then..pushed into place at each corner....no probs then....spacers can be grouted over you know...

[365drills]

We ply lined the floor onto a softwood frame. Then Bal tanked it. And finally laid the porcelain tiles over the lot.

Bespoke work. Custom fit. I will have a look at the pics and comment when I can get more time but at the moment we are upto eyeballs with exhibition stuff. R.