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

2022-01-01 22:19:40

With us, dehumidifiers were brought in with or immediately after the screed to prevent mold. I also continuously monitored the humidity and temperature. Despite the dehumidifiers, it took several days to get the humidity below 90%. And when the heating was turned on, it went back up to 100% for a few days. Only a week later were we at 70%.

The only help is to open all windows at least in the morning and evening, "vacuum" the windows and wipe everything dry where droplets form, ...

2022-01-01 22:47:52

There is no better weather than "winter" for airing out.

You are using a 15 kW heating element?

Our winter here in the south is currently 8-10 degrees with continuous rain ;).
But today was great. 15 degrees and sun.
Now the windows are at least no longer soaking wet in the mornings.

22 kW € quick burner see picture.

2022-01-02 08:31:59

The humidity outside is very high at the moment. For airing out, a temperature difference is needed. Warm air – which absorbs more water – goes out, cold air – which absorbs less water – comes in. Due to the temperature increase, you have to be careful not to let even more moisture in through airing. I would urgently set up a dehumidifier, mobile heater, and mechanically dry all the condensed surfaces meanwhile. You need a temperature gradient.

Example
Temperature absolute air humidity relative air humidity
0 degrees 40% 1.94 g/cubic meter
10 degrees 40% 3.76 g/cubic meter
15 degrees 40% 5.12 g/cubic meter

2022-01-03 08:29:02

You need a temperature gradient

It's not really the gradient, but the heating of the cold air. In other words, without the heater running, drying doesn't work much. Otherwise, I can only use the effect "Warm Air Out, Cold Air In" once.

2022-01-04 10:01:15

To bridge the time between the screed application and the connection of the heating or heating program, it actually doesn't take much to protect your building. 2 dehumidifiers and 2-3 circulating fans should be enough for most. Simply put the dehumidifier's drain hose into the drain. The 2-3 kW/h waste heat from the dehumidifiers warms the building at least slightly, and condensation on the ceiling and windows stays within limits. I paid a rental fee of €50 for 2 weeks for my dehumidifier and about €80 for electricity. I would really spend the money. Or why have you already been waiting since mid-December? I would have set it up 2-3 days after the screed.

2022-01-04 10:05:34

To bridge the time between screed installation and the connection of the heating or heating program, it actually doesn’t take much to protect your building.
2 construction dryers and 2-3 circulating fans should be enough for most. Simply put the dryer’s wastewater hose into the drain.
The 2-3 kW/h waste heat from the dryers warms the building at least slightly and keeps condensation on the ceiling and windows within limits.
I paid a 50 euro rental fee and about 80 euros for electricity for my construction dryer for 2 weeks.
I would really invest the money.

Or why have you been waiting since mid-December? I would have set it up 2-3 days after the screed.

Thank you very much for all the answers – they really helped me a lot! Yesterday I had an on-site conversation with the contractor and a civil engineer friend who happened to be passing by – conclusion: no damage in terms of mold infestation has occurred yet, but since 8:30 a.m. today three construction dryers are running in the house. Thanks again to you all for the input!

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

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