wet room floor tile adhesive

[ukpaul]

I suppose if I search hard enough I will find the answer to my question, but I need an expert just to tell me. I have recently finished tiling a wet room area and the floor tiles have started to lift. I followed manufactures recommendations and even left the tiles un walked on and un touched for a few weeks before grouting. I used wickes own brand powder tile adhesive to fix the tiles originally. At the moment the tiles have started to lift. I'm not going to re fix them until they are completely loose.

Can some one recommend a suitable high quality floor tile adhesive ( marble tile) and quick quide on preperation and time required to cure before grouting or wetting. Pre annoyed at the moment as I did not rush this project and up until today things where looking good.

 

[Richard C]

The adhesive you used is not the worst but it’s probably not the best either. I use BAL but Webber, Mapei (but not the stuff in B&Q), Ardex to name a few are all quality trade products.

The reason your tiles are failing is due to one or more of the following;
• Incorrect adhesive/grout – you must use a quality trade flexible cement powder addy & flexible grout
• To much flex in the floor – insufficiently rigid tile base is the most common cause of failure
• Poor preparation/choice of flooring base
• Incorrect use of primers (hope you didn’t use PVA) – most decent cement addy’s don’t need primer.

You don’t say how long it has taken for the tiles to fail but wet room floors & around ½ way up the walls should also be tanked or at least taped if waterproof backer boards/formers were used. You cannot rely on waterproof addy/grout, it’s only waterproof in the sense that it won’t fail when wet, it still absorbs water & unless you have a waterproof tile base underneath or it’s tanked your tiles will fail. All adhesives I know of should be left 2 weeks before you can use the shower.

If you post more information on exactly what you did & what materials you used I will almost certainly be able to pinpoint what went wrong; or have a serious look at the tiling sticky & through the archive posts & come back with specific questions.

 

[ukpaul]

Thanks for the quick reply. The floor is basically original joist (300mmm centers cant remember dimensions, 1920s house) which have been cross spanned with 100mm x 50mm joists at 250mm centers. This has been over boarded by 18mm MDF. This is overlayed with a Wickes Wetroom base which covers the full area of the shower floor. The floor feels really solid to stand on and doesn't seem to stress in any direction.

The whole room was then sealed with Bal Primer and jointing tape. Then again the whole room was then tanked with 3 coats of Bal Wp1 Tanking sealent. I have had no leakage problems just failure of tile adheasive below floor tiles.

The wetroom has been in use for about 8 weeks with around 4 weeks prior to this setting time after fixing.

Bal Primer

• ukpaul
• 11 Dec 2010
• 1

Bal WP1

• ukpaul
• 11 Dec 2010
• 1

Bal Wp1

• ukpaul
• 11 Dec 2010
• 1

Floor tiles

• ukpaul
• 11 Dec 2010
• 1

 

[Richard C]

Hmm, the only mistake you seem to have made is in the use of MDF. Chipboard is bad enough but that stuff is even worst, a big no, no even if it’s being covered up, it'll just evaporate if it gets damp; always use WBP, seal the back & edges with acrylic primer & screw through into the joists every 150mm. Wet room base formers must be fully supported, 8 weeks is a pretty rapid failure but if you say there is no flex & you tanked with BAL WP1 then my suspicion turns towards the addy/grout you used or the way you laid it. Having used BAL tanking, why on earth didn’t you use BAL addy - either Natural Stone, SPF or Rapidflex + Supaflex grout; it’s always best to use quality products from the same stable. Was the Wickes stuff flexible? Was it suitable for Marble? What type of trowel did you use? - a thick bed solid bed trowel with 20mm round notches, 10mm deep, at 28mm centres or the tiles won’t be fully supported. How thick did you lay on the WP1? Did you prime it with anything before tiling?