Identifying Anhydrite Screed

[grumpygrouter]

There has been a couple of threads recently where Anhydrite Screed has been talked about.

It is known that these type of screeds can be hard to identify, especially for the inexperienced.

Can anybody offer a sure fire way of identifying this type of screed?

 

[Alan.P]

A very good write up of it here

 

[LM Ceramics]

good thread that russ

 

[Gazzer]

They are tricky to identify for certain but if in doubt prime twice with Mapei G primer or other suitable product and teh second coat should go over the first at 90 degrees andle so as to make sure of totally coverage.
Remove any laitance first though.

 

[grumpygrouter]

They are tricky to identify for certain but if in doubt prime twice with Mapei G primer or other suitable product and teh second coat should go over the first at 90 degrees andle so as to make sure of totally coverage.
Remove any laitance first though.

Is that identifiable Neale?

 

[Gazzer]

Every time i have come across it, it has been easy to identify as a loose crust or sometimes a fine film of softer substance that you can usually scrape off with a trowel or something similar.

 

[DHTiling]

Every time i have come across it, it has been easy to identify as a loose crust or sometimes a fine film of softer substance that you can usually scrape off with a trowel or something similar.

And almost white in colour......

 

[Gazzer]

And almost white in colour......

Yep and when you scrape it away and sweep the remains up it has always looked and felt to me like very fine soft powder.

 

[brian c]

is it almost chalky?on top

 

[Gazzer]

is it almost chalky?on top

yep something like that

 

[brian c]

couldnt find anything more about it other than what Dave and Alan posted..webber.

 

[grumpygrouter]

Yes i have got it in my Webber manual here. Was really hoping someone might have had a dead cert way of identifying it. Still time yet I suppose......

 

[DHTiling]

Another tell tale sign russ, is a floor like a bowling green.....no usual snots at the edges and corners.....and that distinctive gypsum smell.....