Hi Guys,

I do apologise as this is a basic thread but to a DIY-er tiling has never been so complicated! Ive read threads on this site for hours so could I check ive got it right? Im tiling travertine onto 7sqm of joists with 18mm P5 chipboard, 10mm Marmox, (BAL tech advice say use 10mm Marmox over 18mm chip is fine) Bal primer, Devimat UFH, Mapei renovation SLC, BAL SPF adhesive, BAL WP1 tanking kit over a Tuff form tray. So....

18mm T&G chip over the whole floor (extra noggins, screwed down min 300mm centres) 10mm gap at corners of room.
Bal primer on top/sides/underneath of chip?
Tuff form tray (18mm) screwed down as per manufacturers recommendations.
For the rest of the floor...2mm SPF then Marmox on top screwed to 150mm centres.
Devimat down (self sticking) - ive read Marmox doesnt need priming first?
Mapei SLC to about 5mm (to cover the 3mm UFH cables plus a bit more).
SLC up to the edges of the Tuff form tray which will give the same level, use the BAL tanking matting over the (up to 1.5mm) gap.
WP1 the corners & tray waste.

Then just the easy bit...the tiling!!!

I hope ive got my head round it now, please point out anything ive got wrong/missed out. Thanks.

Sand the tray to get a good key to it.

4mm min on adhesive for sticking the boards down..

I would use 18mm ply instead of chipboard and a 5mm trowel for fixing the marmox before screwing down with screw's and washers and 300 centre's for the screws would be more than adequate. I would also use scrim tape on the staggered joints of the marmox.


Created on iPhone.....

Thanks chaps, I've read about sanding the tray - thanks, and I should be getting plywood but im keen to use what ive got, I'll see what I can do. Even with ply I'd still have to use Marmox or some other insulation board and with Bal saying my plan is Ok then I might just stick with what ive got. Ref the scrim tape, can I use normal plasterboard joint tape rather than the expensive waterproof stuff?

You can't use normal scrim as the cement in the addy and slc just rots it.....


Created on iPhone.....

Ive bottled the chipboard and instead got some 18mm marine ply which will be going down when ive sorted the shower waste. Quick question about the plasterboard walls... The BAL WP1 is good for tanking about 4.5sqm, tape for the corners and round the drain and shower knobs, ive read when tiling onto plasterboard its best to skim it as the load weight is better or is it best to get aqua board or just more marmox?

Basically I dont want to fall at this last planning hurdle so just picking your brains to do whats best.

Thanks in advance for any replys.

Originally Posted by ollymonkeynuts

Ive bottled the chipboard and instead got some 18mm marine ply which will be going down when ive sorted the shower waste. Quick question about the plasterboard walls... The BAL WP1 is good for tanking about 4.5sqm, tape for the corners and round the drain and shower knobs, ive read when tiling onto plasterboard its best NOT to skim it as the load weight is better or is it best to get aqua board or just more marmox?



Basically I dont want to fall at this last planning hurdle so just picking your brains to do whats best.

Thanks in advance for any replys.

The load weight goes down when you skim plasterboard.......Marmox would be best IMO

Thanks for the quick reply, I'll Marmox the back wall (with the shower knobs on it), what do you suggest for the other side wall which is currently plasterboarded and skimmed? Can I just BAL primer it? or is it best to Marmox this wall also so the whole shower area is done?

Would it then just need the edges/joints taped then tile away? Ive read the Marmox doesnt require priming?