temp of calcium screed before tiling

[kevinz3]

hi
anyone tell me what the procedure is before tiling on to cal/sulp screed with underfloor , do i turn heating off before tiling or leave it at 10 degrees any info would be much appreciated

 

[Sean SML Tiling]

Remove latiance
Commission ufh
Once commissioned then screed should be 75%rh before tiling
Ufh should be turned off 24hrs before tiling

 

[kevinz3]

hi
thanks for info , just a few more to ask, 1 , how many coats of primer should i put on screed?, 2 what is the best material to be shower tray down on to screed? and 3 joiner has fitted certified marine ply to shower walls , is that a no no and should i change it to aqua panel ?, thanks again

 

[Ajax123]

As above other than we always recommend turn the heating off 48 hours before doing a moisture test the tiling if dry.

 

[Perry]

Joiner has fitted certified marine ply. Well he should be certified then. :ban:

 

[kevinz3]

hi
thanks for that but not helpful

 

[J Sid]

Surprised they haven't ask the chippy to do the tiling as well

 

[kevinz3]

anyone got some constructive info please

 

[Ian]

What adhesive are you using on the screed? With regards to the shower, I wouldn't tile onto ply in a shower area, either tank it first or replace with Aqua panel or similar.

 

[kevinz3]

hi
thanks, i am using keraquick on floor with latex added , just need to ask how many coats primer g it needs, would the ply be ok with a waterproof coat then , and what would be best to use

 

[Stef]

As Bri asks, what adhesive are you using?
I would be using a gypsum compatible addy, AnhyFix being my preferred choice.
One coat of TileMaster primer plus diluted 4:1 is what I've found best.

 

[Ian]

As Bri asks, what adhesive are you using?
I would be using a gypsum compatible addy, AnhyFix being my preferred choice.
One coat of TileMaster primer plus diluted 4:1 is what I've found best.

Ditto. In my humble opinion a gypsum based adhesive is the only way to go, I wouldn't even consider anything else.

 

[Stef]

Ditto. In my humble opinion a gypsum based adhesive is the only way to go, I wouldn't even consider anything else.

I used Bal rapid set a couple of weeks ago to push a job on, 6 coats of primer till it stopped soaking in to the screed.
Time will tell but the tiles seem well fixed.

 

[kevinz3]

hi
thanks, i am using mapei keraquick on floor with latex added , just need to ask how many coats primer g it needs, would the ply be ok with a waterproof coat then , and what would be best to use

 

[Ian]

Couldn't tell you about the primer, it'll perhaps say on the bottle, if not, ring mapei technical. With regards to the tanking, I think I'd choose ardex wpc over ply.