Too much moisture in the single-family house after screed installation? Risk of mold?

2022-02-09 11:43:01

And don't forget, -2 degrees and damp is something completely different from 15 degrees and damp. Cold air can be as humid as it wants, but when warmed to 20 degrees, it is dry

2022-02-09 11:43:50

Ah ok, it feels like it’s raining nonstop here (slightly exaggerated). I’m already growing webbed feet and gills

Crazy.. We also have really good forecasts for the next days/weeks. Rare rain, lots of sunshine and temperatures between 5-10°C – that of course makes the homebuilder happy during this phase :D That’s why you first go skiing on the weekend... You have to adapt to the season somehow xD

2022-02-09 12:27:01

The main problem was described in detail a few posts earlier.

The trades must continue, the planning goes on, and the client wants/must move in.

[B]It couldn't be described better.[/B]
The drying out of a building is physically not possible in the times demanded today. It is also not healthy.
The builder is only led to believe that it would work. However, he then also suffers the damage.

The houses are, as already mentioned, completely sealed off and built without natural breathing. Vapor barriers, vapor retarders, lots of silicone, foam sealants, or adhesive tapes are used. And then people complain about why everything is so expensive.

But nobody needs exactly that. Nobody needs Styrofoam either. Why not build a proper exterior wall with a healthy 36 cm Poroton brick, plastered inside and outside with lime cement, and done. Lowest material costs with the best results.

But no, instead we build a 17.5 cm wall and then put 20 cm of Styrofoam on it.
Of course. First, I need much more material, and as a company, I earn much more. 1 square meter of ETICS is charged at 100 euros.
1 square meter of lime cement plaster with maybe 20 euros. No matter.

2022-02-09 13:15:13

But nobody needs exactly that. Nobody needs Styrofoam either. Why not build a reasonable exterior wall with a healthy 36 cm Poroton brick, plastered inside and outside with lime cement, and done. Lowest material costs with the best results.

Please give numbers on how much heat is lost in each case and how much water passes through!

2022-02-09 21:31:07

The main problem was described in detail a few posts earlier.

The trades must continue, the planning continues, and the client wants/must move in.

[B]It cannot be described any better than this.[/B]
The drying out of a building is physically absolutely impossible in the times demanded today. That is also not healthy.
The client is only led to believe that it would work. But then he is the one who suffers the damage.

The houses are, as already mentioned, completely sealed off and built without natural breathing. Vapor barriers, vapor retarders, lots of silicone, foam, or adhesive tapes are used. And then people complain why everything is so expensive.

But nobody needs exactly that. No one needs Styrofoam either. Why don’t people build a proper exterior wall with a healthy 36 cm Poroton brick, plastered inside and outside with lime cement, and done. Lowest material costs with the best results.

But no, we prefer to build a 17.5 cm wall and put 20 cm of Styrofoam on top.
It’s obvious. First, I need much more material, and as a company, I earn much more. 1 square meter of ETICS is charged at 100 euros.
1 square meter of lime cement plaster with maybe 20 euros. Doesn’t matter.

That was also our approach: keep it simple! 36.5 cm wall, lime-cement plaster, double-glazed windows, cold room floor. After almost 2.5 years, so far no moisture problems with normal ventilation. At night, windows partly tilted with underfloor heating on... screw the 10 € monthly extra cost for gas consumption. Construction costs were correspondingly low. I can race around with energy for 25 years and still have saved money.
The screed contained quick binder additive. The underfloor heating could, I think, start after 7 days with heating protocol. Draft ventilation 3-4 times daily in the relatively cold and dry autumn, wiping windows dry. I believe the screed was dry after 2-3 weeks and tiling could begin. After painting, also ventilate well again. In the house we have 47-51% humidity. When it is colder outside, then in the bathroom, kitchen, and guest WC, windows are slightly fogged (approx. 1-2 cm at the lower window/window frame). But that should be normal.

2022-02-22 10:40:11

After the screed drying with us (which should be finished this week), 2 wooden beams in the attic were affected by black mold. Directly one day later, after my remark to the general contractor, this was sanded down and "treated". However, the black spots are still slightly visible on the wooden beam.

Does anyone here have experience with mold? How is this usually removed? Sanding + chemical treatment and done? Could it possibly come back after a few months, since the mold presumably still remains in the wooden beam? How does one deal with something like this?

This probably happens more often these days...

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Too much moisture in the single-family house after screed installation? Risk of mold?

WilderSueden

Prager91

Durran

RotorMotor

Georgian2019

Prager91