Hello everyone,
I urgently need some advice.
We have a house that we bought in 2019 and partially renovated. All the windows are new with double glazing, and we installed underfloor heating.
In recent years, we have already experienced high indoor humidity levels, up to about 65% in winter.
This year, we even had high humidity of 55-65% in all rooms during the summer, and ventilating did not help. Now, in autumn, the humidity is rising above 70%, and we are gradually becoming unsure of what to do.
I measured the walls in all rooms with a moisture meter. The north-facing wall shows about 16% moisture in the corners. The interior walls have about 12%. However, there are no walls that are visibly wet. The roof and walls are also tight.
We regularly air the rooms by cross-ventilation, morning and evening, and now have a dehumidifier running in the bedroom. Still, mold is beginning to grow.
The north basement wall is also damp, but there is roofing felt between the stones, so I don’t think the moisture is rising from below.
Additionally, last year I insulated the basement corner with EPS insulation boards.
I believe I have covered all relevant details.
Does anyone have any idea what I might be doing wrong or where I should look next?
Best regards,
andre007
I urgently need some advice.
We have a house that we bought in 2019 and partially renovated. All the windows are new with double glazing, and we installed underfloor heating.
In recent years, we have already experienced high indoor humidity levels, up to about 65% in winter.
This year, we even had high humidity of 55-65% in all rooms during the summer, and ventilating did not help. Now, in autumn, the humidity is rising above 70%, and we are gradually becoming unsure of what to do.
I measured the walls in all rooms with a moisture meter. The north-facing wall shows about 16% moisture in the corners. The interior walls have about 12%. However, there are no walls that are visibly wet. The roof and walls are also tight.
We regularly air the rooms by cross-ventilation, morning and evening, and now have a dehumidifier running in the bedroom. Still, mold is beginning to grow.
The north basement wall is also damp, but there is roofing felt between the stones, so I don’t think the moisture is rising from below.
Additionally, last year I insulated the basement corner with EPS insulation boards.
I believe I have covered all relevant details.
Does anyone have any idea what I might be doing wrong or where I should look next?
Best regards,
andre007
It is clearly a thermal bridge issue. The windows are no longer the coldest spots, but the wall is. Additionally, the new windows are probably more airtight than the old ones, so there is no longer any natural ventilation. -> Condensation occurs at the coldest points in the most frequently used rooms.
Therefore: increase ventilation (twice a day is not enough). Or increase heating or use active dehumidification.
Therefore: increase ventilation (twice a day is not enough). Or increase heating or use active dehumidification.
andre007 schrieb:
Hi, the walls were not renovated.The classic problem: new windows installed in old, uninsulated walls. The uninsulated walls are colder than the new windows, causing moisture to settle on the walls and mold to develop.
The north-facing wall will be the coldest, but this applies to all exterior walls.
The new windows also reduce natural ventilation. This can be improved by adding trickle vents.
You should definitely consider taking measures to insulate the walls.
Thank you for the feedback.
As mentioned, we are considering blown-in insulation. For this, I calculated the construction build-up using Ubakus (attached) and noticed that condensation accumulates in the insulation. I am concerned about making this worse. Adding insulation on the exterior facade is currently not financially feasible.
Has anyone had experience with blown-in insulation and can share their insights?
Best regards, Andre
As mentioned, we are considering blown-in insulation. For this, I calculated the construction build-up using Ubakus (attached) and noticed that condensation accumulates in the insulation. I am concerned about making this worse. Adding insulation on the exterior facade is currently not financially feasible.
Has anyone had experience with blown-in insulation and can share their insights?
Best regards, Andre
andre007 schrieb:
Insulating the facade is currently not financially feasible.Then the only options left are blown-in insulation and increasing the room temperature to 22–23°C (72–73°F), while keeping furniture away from the exterior walls.Nida35a schrieb:
Then the only option left is blown-in insulation and increasing the room temperature to 22–23°C (72–73°F), keeping furniture away from the exterior walls. Thank you for the information. I have uploaded it as images.
W
WilderSueden4 Nov 2023 22:02Retrofitting decentralized ventilators with heat recovery. Window rebate ventilation is problematic and hardly deserves to be called even a temporary solution. Why install new, well-insulated, and airtight windows only to compromise them again with drafty trickle vents?
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