ᐅ Installing Vinyl Flooring Over Anhydrite Screed at 50-70 Digits?

Hi,

We had an anhydrite screed installed in a prefabricated timber frame house on February 19. It is currently in its 7th week of drying!

A measurement taken yesterday showed 55 diggits in one corner of the living room, sometimes lower, but in some areas up to 70 diggits.

We have underfloor heating. The drying program has been running for 7 weeks, with an average room temperature of 28°C (82°F) and 15% humidity.

The screed was only ground down 2 weeks ago.

All appointments are firmly scheduled. The kitchen is arriving next Wednesday, and the vinyl flooring is supposed to be installed just before that.

The screed is planned to be primed first and then skim-coated. The vinyl will be laid 2 days after that.

Is this still feasible with these moisture values? The flooring installer said that not much can go wrong since the screed is not completely sealed, and any residual moisture can escape through the joints or expansion gaps.

What could happen in the worst-case scenario?

Thanks in advance!

Nothing much will happen. It will just dry a bit more through the joints and the missing baseboards, and that’s fine.

Did he only measure with the digital device and not take a CM measurement? Normally, floor layers are always keen to comply with the laying tolerances and document them reliably with the CM measurement. Ours only started laying once the CM measurement values were confirmed to be correct.

No, he doesn’t have a moisture meter.

My main concern now was just what could potentially happen if there is still some residual moisture present.

I know that the floor installers take the measurements themselves and are responsible. There is no other way, otherwise important deadlines would be delayed.

It also depends on the vinyl. With solid vinyl, I wouldn’t worry. On HDF substrates or with a cork layer, it could retain moisture for too long and start to rot.

So, the vinyl flooring is as follows:

The floor has already been primed and leveled:

As I said, I hope this wasn’t a mistake.

I just wanted to hear from you if there is any experience or knowledge regarding this approach.

Thanks in advance for your opinions!