What is anhydrite cement?
Cement screeds can be used in wet areas (without any restrictions) and outdoors. From the chemical point of view anhydrite is anhydrous calcium sulfate (CaSO4) – a binder which is very similar to gypsum (formed by dihydrate calcium sulfate – 2H2OCaSO4).
How long does it take for anhydrite screed to dry?
about 49 days
Where the screed is thicker, or with poor drying conditions – pretty usual for the UK – drying times can be significantly increased. This means that a typical anhydrite screed dries in about 49 days – compared to around 21 days for Ordinary Portland Cement.
Can you tile on liquid screed?
It is recognised that all Anhydrite liquid screed floors have a weaker surface layer than traditional sand cement screeds and good preparation is required for any floor covering. Before tiling, the area must be fully dry to ensure the adhesive will adhere to the tile and floor screed without issue.
Why is anhydrite used in a floor screed?
Anhydrite is widely used in floor screed applications because of its numerous advantages : better fluidity for self-levelling, greater dimensional stability, high mechanical strength and outstanding thermal conductivity.
How is anhydrite used in the construction industry?
In construction, anhydrite can advantageously replace traditional cement, as a binder for screed mortars. Anhydrite is widely used in floor screed applications because of its numerous advantages: better fluidity for self-leveling, greater dimensional stability, high mechanical strength and outstanding thermal conductivity.
What kind of primer to use on anhydrite floor?
Rapid-drying acrylic primer for tiling onto plaster walls and plasterboard, anhydrite screed floors and cement floors. Synthetic-resin-based water-dispersion primer for treating gypsum surfaces prior to fixing ceramic tiles.
How long does it take to sand anhydrite floor?
If you are using a final floor finish which will be fixed to the screed’s surface using an adhesive then you will need to lightly sand the laitance off the surface of the screed before using a compatible primer and adhesive. We recommend sanding your screed floor between 7 to 10 days after installation.