Make life easy, search the forum.

Discuss Anhydrite not dry in the Tiling News; Tile News area at TilersForums. USA and UK Tiling Forum

Please checkout the following advertisement.
Good Evening All.

Had been making plans to hopefully start the tile of a anhydrite floor at the end of the week but the first readings from the digital hygrometer is it floating between 87-90 rh.

The screed went down in December and has different depths the deepest I believe is 90mm so quite thick.

I have commissioned the system and ran it 10 days on maximum and turned it off a week ago.It has been on and off before I appeared.

Not been the greatest weather for opening all windows for ventilation and also windows shut at night for security so some of the moisture may have sucked back into the screed.

It has been sanded and I will be using gypfix and ditra.

Question is the what is the best and quickest way to reduce the rh?,bring the floor up to max again for 3 days and allow to cool or maybe even hire some humidifiers if this works or any other ideas.

Also what is the true technical reasons that floors fail when the moisture content is to high?

Other trades on site proving a pain as they see if it must be fine as one can walk on it!


Cheers all.


Kevin
 
OP
K

kaharrison9

So in theory could 85 rh be accepted if ditra is used as any moisture entrapment under a large format marble tile would not interfere with the screed as the ditra would form a physical barrier and I assume the moisture would then naturally come up and evaporate through the stone before it has been sealed.
 

Ajax123

TF
Arms
Reaction score
933
So in theory could 85 rh be accepted if ditra is used as any moisture entrapment under a large format marble tile would not interfere with the screed as the ditra would form a physical barrier and I assume the moisture would then naturally come up and evaporate through the stone before it has been sealed.

No mate. If you use ditra over a wet screed the last thing you want is the moisture coming up through the stone as it will stain it. You would need to tape the ditra joints and let the mat do it's thing. In theory 85% would be fine but you need to find what you can stick it down with. Possibly gypfix, Anhyfix or one of the other stable of gypsum adhesives.
 
Reaction score
309
Sounds an interesting project Kevin, Whats the gypix costing per bag?

Have you looked at TileMasters Anhyfix?

States this in the attached link
"Anhyfix can be applied to anhydrite/calcium sulphate screeds with 85% Relative Humidity (RH) or less. Anhyfix can be applied directly to anhydrite/calcium sulphate screeds"

[DLMURL="http://www.tiletown.co.uk/published/39/resources/documents/AnhyFixTechData.pdf"]Anhyfix Data Sheet [/DLMURL]

Anhyfix Technical Guide
 
Last edited by a moderator:
OP
K

kaharrison9

Hi Lee

Thanks for your response.

Have loosely heard of Tilemasters anhyfix but up to know have had no failures using the Gypfix and Ditra combination on anhydrites so am slightly reluctant to change also on this job I have purchased the https://www.tilersforums.com/forums/tile-adhesive/ and would be charged 30% restocking

I do have a 200 m2 coming up soon where the customer is sourcing the materials so there may be an opportunity there to try.

Looking at the data sheet obviously the 85rh level is appealing and I fully agree for reasons that a sanded screed should be primed something other gypsum manufactures sell as not necessary.

If okay to mention I pay around ÂŁ23.00 per bag-is that near the anhyfix price also is it available locally?

Is there any issues adhering to uncoupling membranes?

Regards

Kevin
 
Reaction score
309
Hi Kevin, Supplied Anhyfix to a few of the other forum tilers, judging by posts made re usability and performance i would say it was a great product.

For a 200m2 project, price would be sub ÂŁ20 per bag.

Dont forget that TM also do a Anhydrite Leveller now as well. (AnhyLevel)
 
OP
S

Stef

Both Anhyfix & Anhylevel are very good products.
Anhyfix stick like the proverbial.
Anhylevel is strange at first as it's a white slc & not the normal grey, it performs as well if not better than the other slc I have used.
 
Reaction score
309
Both Anhyfix & Anhylevel are very good products.
Anhyfix stick like the proverbial.
Anhylevel is strange at first as it's a white slc & not the normal grey, it performs as well if not better than the other slc I have used.

So......you would definitely use TM Anhyfix again Stef?
 

Reply to Anhydrite not dry in the Tiling News; Tile News area at TilersForums.com

Or checkout our tile training advice or the Tile Standards

This website is hosted and managed by www.untoldmedia.co.uk. Creating content since 2001.

UK Tiling Forum Stats

Threads
66,599
Messages
866,700
Members
9,508
Latest member
sj1709
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock