Tiling on a skimmed bathroom wall - HELP!

[sg0102]

Hi there,

I am in the middle of refitting my bathroom, and it is the first job i have done - i am trying to do the tiling myself.

Now, the old tiles came down, and the wall needed reskimming, which we have just had done.

My questions is can we now tile on top of this wall, with just waterproof adhesive on the tiles? Or do we need to put some sealant down first? We have started, without any sealant, but my Dad has just told me i need to seal it?

Can someone please advise (asap!?) - and what is the risk of not sealing?

Many Thanks

 

[DHTiling]

What is the adhesive you are using.?

how long was it since the wall was skimmed..?

And what size tile are you using..?

 

[sg0102]

Hi,
I'm using Unibond adhesive, waterptoof stuff. The skimming was done days ago.

Thanks
Steve

 

[DHTiling]

what size tiles are they...?.

when you say day's..how many please...?

 

[sg0102]

Sorry, the skimming was done on Thursday - some bits are a bit patchy still, but most looks dry. (Plasterer said it would be dry to tile in a couple of days).

The tiles are 41cmx30cm big.
THanks for your help

 

[DHTiling]

Hey no probs..........

Firstly.....that skim isn't dry enough...don't you just love it when another trade sez it will be OK....what is the skim onto..substrate wise....is it plasterboard or basecoat.?

The tiles are too big to be using a tubbed dispersion adhesive IMO, you will need to be using a cement based adhesive...are the tiles ceramic..?

 

[sg0102]

Thanks!

Yeah, i do love it!
The skim was onto plasterboard. How long should we be leaving it do you think?

The tiles are ceramic yes...

 

[DHTiling]

Thanks for be patient.....It will be fine to tile next week.....The skim not only needs to loose it's moisture but it also needs time to gain strength....2 weeks from the finish date of skimming will be ideal on plasterboard.......

good luck...

 

[sg0102]

Thats great, thanks Dave.

Another question, do i need to put any sealant down first? or can i tile on to the skimmed wall?

 

[DHTiling]

Sorry about that.......yes you need to use an acrylic tilers primer to seal the gypsum from reacting with the cement based adhesive you need to use.....if you do use a tubbed adhesive then no need to prime BUT it will take a whole lot longer for the adhesive to dry out.....

Tubbed dispersion adhesives need to loose their moisture with air contact...where as the cement based adhesive will dry hydrolicaly within a set time period, depending on whether the adhesive is rapid setting or standard setting....

The tubbed one could take days to properly dry....

hope this has helped you.....