The best primer and Adhesive for anhydrite screed - TilersForums.com

[Ajax123]

You will rarely see movement joints in anhydrite. However if the tile face needs a joint e.g. Large bays, door thresholds, etc this these should be installed regardless of whether or not you see a joint in the screed. Sometimes the joints are not required in the screed and sometimes they are just beneath the surface of the screed so you can't see them. Not ideal I know but it is the best way for the screeders.

 

[Stef]

Alan, I actually quoted you to the builder & was going to pass on your number to him as I knew you would verify what I was explaining to him.
Thankfully it never got to that stage as I know him & he knows what I'm like when it comes to anything tile related.

 

[Sean SML Tiling]

You will rarely see movement joints in anhydrite. However if the tile face needs a joint e.g. Large bays, door thresholds, etc this these should be installed regardless of whether or not you see a joint in the screed. Sometimes the joints are not required in the screed and sometimes they are just beneath the surface of the screed so you can't see them. Not ideal I know but it is the best way for the screeders.

When separating the floors in bays is it ok to use a 3mm silicone joint as a movement joint?

 

[Ajax123]

When separating the floors in bays is it ok to use a 3mm silicone joint as a movement joint?

Yes that's ok provided the floor doesn't expand by. More than about 2mm. Movement joints though are usually 5mm in my experience

 

[Sean SML Tiling]

Ok on anhydrite screed 80mts and I've separated the floor 6 bays as there is 6 uhf zones. Customer didn't want industrial joints and went for silicone.

 

[Ajax123]

Ok on anhydrite screed 80mts and I've separated the floor 6 bays as there is 6 uhf zones. Customer didn't want industrial joints and went for silicone.

The screed itself hardly moves so that bit will be fine. Can't say for the tiles though.

 

[Dave]

That size of movement/expansion joint isn't suitable for floor Installations imho .. But I have seen it done , might work for small areas with a joint in a doorway , min I would install for neatness is 5mm cold joint or larger areas , a preformed 10mm joint.

 

[newlineuk]

Do you guy's grind the laitance off first?

 

[Ajax123]

Do you guy's grind the laitance off first?

If you don't you ain't doing it right... :mad2:

 

[Stef]

As Alan (Ajax) says, you must remove the laitance or the floor will fail!!!