Click vinyl and residual moisture in the subfloor, how high is the risk?

Hi,

I am quite desperate and looking for advice and maybe some reassurance.

Last week we moved into our house. The floor coverings were done on our own, the rest by companies. Unfortunately, before the tiles and vinyl came into the house, I forgot the CM measurement. I even had it on my mind, then our daughter was born and along with the construction stress, I completely forgot this stupid measurement. I have been blaming myself for it ever since.

I am very afraid that this will be my downfall and I can’t enjoy the beautiful house. Between the screed installation and the start (not completion!) of laying the floor (click vinyl and tiles, including grouting and baseboards, which I unfortunately also sealed nicely with silicone...) there are about 14 weeks for the upper floor and even 19 weeks for the vinyl on the ground floor, tiling began after 13 weeks..

A few technical details:
- Calcium sulfate screed, 60mm on the upper floor, 70-80mm on the ground floor
- Underfloor heating
- Click vinyl on the upper floor with MDF carrier, full vinyl on the ground floor, both with impact sound insulation and PE foil underneath
- During the drying phase (April to July) of course ventilated and heated, but since it was extremely rainy and wet, the drying did not progress very quickly, so we dried for another 4 weeks with three construction dryers and three fans in addition
- Construction manager only measured the surface and considered it dry
- Screed installer is also confident, but of course I get nothing in writing

I know it’s my own fault and I blame myself the most.

Regarding my questions
- I know it’s a crystal ball, but how realistic is it that there is still so much moisture in the screed now to damage the building?
- What would be the worst case? Loss of the floor? Mold? Can you notice something like mold?
- Is there a way, so that I can finally sleep again, to measure something afterwards? I can hardly take the floor out in the middle of the room, can I?
- How should I best proceed? Get an expert? Wait?

I thank you from the bottom of my heart!

Maybe can calm you down a little.

Crystal ball, but how realistic is it that there is still so much moisture in the screed to damage the building?

Very unrealistic.

Can you notice something like mold?

Just look under the vinyl. I would be even more relaxed with the tiles.

How should I best behave? Get an expert? Wait?

Take a deep breath and enjoy the new house. Do nothing.

No one will give you a guarantee, but with the time including forced drying, it would be very unlikely since the residual moisture is relevant. Especially since some of the mentioned floor coverings, like tiles and full vinyl, are rather insensitive to residual moisture.

But since we are talking about tiles: I assume you installed them in the bathrooms. Was the floor sealed there beforehand? Who did that? If it was the construction company, they should have conducted a moisture measurement before implementing the sealing anyway.

Hello everyone and thanks for the answers so far. I am a bit relieved…

Regarding the tiles: they were laid by my brother-in-law, he is a tiler. The bathroom was sealed accordingly, however, an additive was also used in the bathroom, where the screed installer’s invoice states in writing that the readiness for covering was guaranteed after 14 days. Therefore, I was relaxed about this so far and did not mention it in the original post.

The guest WC, utility room, and hallway were then tiled as described above, without sealing and measurement.

In the utility room, I still have an open spot down to the floor slab where the empty conduits come into the house. Could a sample of the screed be taken here? One could reach that!

Looking under the vinyl is difficult, as it is clicked in and skirting boards are also in place, so I cannot lift anything at the edges either.

..by the way, there are two full floors without a basement, in case that is still important.