Slate on No More Ply

[Nmidia]

Hi All,

After some advice

We are installing 12mm No more ply on stud walls and 6mm overboarding on the floor. We are tiling 10mm thick natural slate tiles.

#Will the shower area need to have a tanking membrane painted on or will waterproof tape over joints and Nmp mega adhesive between the joints do the job?

#which tile adhesive is recommended? is the BAL natural stone one fully waterproof? The datasheet for the BAL says not to prime the surface which goes against the NMP installation instruction
http://files.building-adhesives.com...C Technical Data Sheets/BAL_Natural_Stone.pdf

#Should I just go for a standard waterproof flexible cement based adhesive? If so, which is best performer?

#Are the mapei adhesives any cop?

Cheers for taking the time to read this!

 

[AdamCH]

No more ply isn't waterproof so would need to be tanked but be aware that many of the liquid tanking kits have a 32kg m2 weight limit. If you haven't fixed it then you might be better switching to Marmox in the shower area which can be waterproofed in the way you've described and doesn't need tanking.

 

[Nmidia]

Thanks for the advice

Isn't using waterproof adhesive plus the primer enough then?

http://www.nomoreply.net/installation/wetrooms/

The NMP site uses the term "completely waterproof" - obviously nothing is but I was hoping that it would be good enough for domestic use!

I must admit that I hadn't realised that the tanking kits had a weight limit, obvious really. The slates have a weight of 28kg per m2 according to the supplier so with adhesive I will be pushing the limits of the tanking kit.

Perhaps Marmox is the way forwards.

Any advice on the adhesive to use?

 

[AdamCH]

Might be best to ring up their technical support and ask them if waterproof really means waterproof.

If they're happy then go with it.

Waterproof adhesive just means that it doesn't fall to bits if it gets wet - it doesn't actually waterproof anything.

 

[tpt]

No need to tank it, no more ply is waterproof if you prime it with 2 coats of sbr and tape the joints -see http://www.nomoreply.net/installation/wetrooms/

BAL is great adhesive, but so is (trade) mapei. stay away from the diy sheds.

Which brands are you able to get (assuming your buying locally?)

 

[Nmidia]

Thanks for fhe confirmation. Have you actually installed like this?

Will be ordering off Internet i think unless i can get cheap locally.
Need to calculate how much i need. Are we talking 6mm racked for slate?

 

[tpt]

not personally, but i own a shop - sell like this all the time for porcelain etc.

For large format slate you'd want a deeper trowel than 6mm, more like a 10mm. Most 20kg bags will yield 4-5m2 coverage, more like 4 with a deep bed. If you use a calibrated slate, you'll make your life easier due to the lack of variation in depth.

We sell granfix and palace mostly, with a bit of mapei to the trade. I'd suggest granfix fastset flexible as a good quality cement based adhesive. We sell shed loads of it, palace is our budget option and some traders just prefer mapei. We are just about to start dealing with Keracol too, they have some great stuff.

let me know if i can help with supply of the slate or any of the consumables you need.