Anhydrate screed prep spec check

[poynton phil]

First time i'v come across a anhydrate screed, and the screed people left these instructions for the tiler (me)So I just want to check if this is the right way to go. The screed is heated, and tiles are 800x800 porcelain

Sand the sheen off the floor, with a floor sander.

Prime with, 1 or 2 coats of SBR.

Tile floor using a SPF ahesive.

Any advice is appreciated. Thanks

 

[Chalker]

First time i'v come across a anhydrate screed, and the screed people left these instructions for the tiler (me)So I just want to check if this is the right way to go. The screed is heated, and tiles are 800x800 porcelain

Sand the sheen off the floor, with a floor sander.

Prime with, 1 or 2 coats of SBR.

Tile floor using a SPF ahesive.

Any advice is appreciated. Thanks

Good advise.
Make sure it's dry.

 

[Stef]

1st thing is check to make sure it's dry, hygrometer, & check when it was poured.
Get it sanded as quick as possible as this will aid drying time. Get windows & doors open to let out moisture from building.
I would give it one coat of TileMaster prime plus mixed at a 4 or 5 to 1 ratio & I would use TileMaster AnhyFix.
I would keep away from a cement based addy on top of a calcium sulphate screed.
There are a few compatible gypsum based adhesives out there, I like AnhyFix & that's what I use when going over a gypsum screed.

 

[nybor62]

the low latence screed does not need sanding so ive been told , gypfix i here is good , not used it myself , deffo not cement based addy imo

and and who ever you get the addy from should also do the recommended primer, and yes check for moisture in the screed

 

[Stef]

the low latence screed does not need sanding so ive been told , gypfix i here is good , not used it myself , deffo not cement based addy imo

and and who ever you get the addy from should also do the recommended primer, and yes check for moisture in the screed

Rob I'm certain the low laitance needs sanded, I can remember a post from Alan about this & he stated all these screeds must be sanded...

 

[CJ]

I checked on a job last week, with the screeder who actually did the floor 10 years ago.

Hemi hydrate. He said do not scabble it, and prime with acrylic primer.

 

[nybor62]

alan should know stef, it was the main contractor who mentioned it to me , it was lafarge screed .

 

[Stef]

alan should know stef, it was the main contractor who mentioned it to me , it was lafarge screed .

If I'm stuck on any kind of screed then Alan's the go to man..
He knows these screeds inside out & will probably reply when he sees this..

 

[Ajax123]

the low latence screed does not need sanding so ive been told , gypfix i here is good , not used it myself , deffo not cement based addy imo

and and who ever you get the addy from should also do the recommended primer, and yes check for moisture in the screed

Yes it does. All anhydrite screeds require sanding. In fact the advice of the tiling association and the contract flooring association is that ALL screeds and concretes require mechanical abrasion as part of the preparation.

My main concern about your having been told it does not need to be sanded is if there is a failure, ALL the adhesive manufacturers instructions say sand it and you say you did not sand it no one will stand side by side with you to defend you.

 

[Rookery]

I'd sand the screed, prime twice and then fix with Keraquick.

 

[Ajax123]

I'd sand the screed, prime twice and then fix with Keraquick.

I would use a gypsum based adhesive to make certain it sticks...

 

[poynton phil]

I will be using a floor sander on this floor, but as anyone any sort of idea, how long it will take, in total there will be about 150msq. Also I'v heard that shower room floors need tanking, is this correcect. Thanks.

 

[Ajax123]

I will be using a floor sander on this floor, but as anyone any sort of idea, how long it will take, in total there will be about 150msq. Also I'v heard that shower room floors need tanking, is this correcect. Thanks.

Sanding should only take a couple of hours. I've done 500m2 in an afternoon before. Not heard that about shower room floors but if the tiles will allow water through it would be a good idea.

 

[mike1979]

As the lads said !!!!! I do loads of them and they are a joy to tile on really flat I sand it of Hoover it and prime it I used to use the granfix gypsum based adhesive but find it sets too slow so I use nicobond gypsum adhesive love the stuff !!

 

[Spud]

Sanding should only take a couple of hours. I've done 500m2 in an afternoon before. Not heard that about shower room floors but if the tiles will allow water through it would be a good idea.

Hi Alan which machine did you use to achieve 500m2 in 4 hrs as the floors I have done taken a lot longer and I have some decent equipment