Travertine on render

[topcarper]

Hi, can someone please tell me whether it is necessary to use an acrylic bonding agent to a rendered wall?

Basically i have a guy doing my bathroom and i am having 30x45x12 trav tiles put up, the walls were originally tiled halfway up with tiles that sat proud of the wall on cement render onto the original bonding, above this the walls are plaster skimmed which the builder was going to bond over to bring it out level to the cement render below until i asked or told him (after reading lots of really helpfull stuff on here) that i thought he needed to use a tile backer board adhesively and mechanically fixed to the wall to tile onto as the plaster skincoat was blown in places and wouldnt hold the weight and also that a bonding coat wasnt suitable for heavy tiles, he was more than happy to do this and has used Dukkaboard which appears to be solid and secure, my only real worry now is whether to use some kind of bonding agent onto the existing cement render where the old tiles were (the builder removed these fairly easily without ripping much of the cement render away) When i bought the tiles i also bought some BAL acrylic primer as i thought it might be worth doing, i have read that PVA is a big no no so i want to make sure the guy is aware of this

Any advice would be greatly appreciated, thanks

 

[White Room]

Giving it a coat of acrylic primer would'nt do any harm.......

Hi and welcome...

 

[cam_low]

Surely if he is not aware of these needs then he shouldnt be tiling !!!!

 

[topcarper]

Thanks Whitebeam for a speedy response

Can i ask you mate, i was also told there is no need to prime the dukka board as this is a cementious style of board, i take it this is correct, also whats the max thickness of adhesive to use for these tiles?

I have also asked the builder to tile down onto a securely fixed batten as he was going to tile down onto the bath but even though its a carronite style which is very solid i was worried that the weight of the tiles might end up slipping on install and flexing the bath, as ive said he is more than happy to listen to the stuff i ask him to do but i guess thats the trouble with getting a builder who does it all as opposed to getting different tradesmen who specialise in the different trades

 

[White Room]

No need to prime the dukka board, just give it a wipe over with a damp cloth to remove any dust that might be there.

The wall tiling would need to set out so you don't end up with slithers anywhere, starting on the bath not such a good idea and a rapid adhesive would be my choice to hold the first few tiles at least.

 

[topcarper]

Hi Cam,
to be honest mate his work has been of a good standard and he came recomended by friends who's son he did a full bathroom refit for and by all accounts did a really good job, i always wanted travertine but it was only after i had bought them that i decided to start reading about them....also after lugging them from the shop to my house and started thinking about the weight!! I might have gone down the ceramic route if i had known what i know now but he says he has put them up before so i can only take his word on that

Also he was going to tile down onto the bath he is fitting which is a carronite type and really sturdy but ive told him i'd prefer it if he would tile onto a securely fixed batten rather than the bath as i dont want the slightest amount of stress on the bath and the weight of these tiles as you well know is fairly hefty, he said he is going to batten onto the wall under the hidden lip of the bath anyway which i was going to ask him to do so i'm sure he knows his stuff as like i have said his work so far has been of a good standard, its just little things that in the end might amount to bigger problems in time

 

[topcarper]

Apologies for repeating myself about the bath, i didnt realise i had written that in the earlier post...its been a long day!!!:sofahide:

 

[nybor62]

also a white cement based adhesive , just make sure ho dont use dot and dab method , if he does show him the door

 

[topcarper]

Thanks for the info

One last thing, when the tiles were ripped off the exiisting cement render there were some small gaps from where the original tileswere pressed onto the cement, well the builder has filled these gaps with plaster bond, i know they are only small areas but was wondering if it would have any impact on when he actually fixes the travertine to the walls?

The adhesive is BAL single part flexible which ive bought five bags of, the area is 22sq mtrs as i know he has to butter the tiles as well as spreading onto the walls

 

[White Room]

I would be tapping the render to see if there are any other hollow points, bonding in very small areas will be ok but prime with the acrylic primer you have.

 

[topcarper]

Ive checked the render and its pretty solid for 95% of it, i will make sure its primed well before the tiles go on

Once again thanks for all your replies...brilliant forum for advice, keep up the good work