Anhydrite Screeds: Are You Confident When Tiling To Them?

[Stef]

Lol, how long has the screed been down?

Pumped in on the 9th of July.

They are pushing to get the floors tiled.
Be about another 6 weeks before the floor is probably ready for tiling.

Got asked today if we could fit some sort of Mat (membrane) to speed up the process.
Can anything be put on a Gyvlon screed to speed up the process?

 

[DHTiling]

NO!!! you can't , the only way to speed up the drying is to force dry it , is it heated,.?

 

[Stef]

It's getting forced dried just now Dave.
The heating has been on for just over 2 weeks.
I told them I didn't think you could do anything else to aid drying but I would ask the question.
It's not been sanded yet, I told them to sand it after 2 weeks but its still not been done.
We will see what they want to do..

 

[DHTiling]

How high have they got the heat..?

 

[Stef]

How high have they got the heat..?

Not sure as they rigged up a small cylinder heater to heat the floor.
It's running almost full pelt & the house is boiling.
The heating will eventually be source fed from below the field out the back of the house with a 10kw heater in the house.
One of these "Green" efficient heating systems.
The moisture in the house was unbelievable a couple of weeks ago, it was running down the insides of the windows.
Windows are open all day now to let the moisture escape.
Guys that were on site today reckon another 6 weeks before the screed will be anywhere near dry.

 

[DHTiling]

That seems a long time .. ? but this does depend on the heat of the screed though ... if it is only say 20dgs then it should be around double that to force it dry in 2 weeks or so , so the lower the temp and poor ventilation , then it will take longer.

 

[Stef]

Dave, I'm going to check in the morning & get them to get it turned up as far as possible.
As soon as the hygrometer was put on the floor it was registering 70+rh, wasn't even on an hour & it was up at 100%.
I reset the box & moved it about 6 feet & sanded a patch for it to sit on.
40mins later & we were almost off the scale again.

 

[DHTiling]

It is no good testing for RH whilst the heating is on 🙂.. false readings ..

 

[Gazzer]

The hygrometer needs to be in place for 24 hours before turning it on, then a further 24 before the reading is taken.

 

[Gazzer]

The heating should be off for 3 days IMO