ᐅ Condensation Under OSB Panels in New Construction, October 2014
Created on: 10 Dec 2014 08:27
M
ml_cool
Hello everyone,
I have been browsing through various forums for several days but only found fragmented information that doesn’t quite match my problem.
On October 1st of this year, I moved into a newly built one-story L-shaped bungalow. Basically, everything is fine so far.
During the construction phase (when the ceiling was still open), I placed 40m² (430 sq ft) of OSB boards on two piles on the ceiling joists to later install them on the future "cold floor" after moving in.
After moving in, I laid some OSB boards in the attic as a walkway to access the roof and to place some boxes on. I placed these directly on the joists; contact between the boards and the insulation cannot be ruled out, as the insulation is almost flush with the joists.
The insulated ceiling structure from the living area side is as follows: 1. gypsum board, 2. aluminum profiles, 3. vapor retarder (blue foil), 4.+5. joists with 200mm (8 inches) insulation wool in between. The roof is uninsulated, essentially a cold attic; insulation is only in the floor ceiling.
Now, after about 9 weeks, I accidentally noticed that some of the boards are significantly wet on the underside (facing the insulation). It clearly looks like condensation. One of the boards already shows slight signs of mold.
My immediate action: I stood all the boards vertically to prevent further moisture buildup and to let the already wet boards dry out.
I have also called the construction company and explained the situation. They advised me to avoid contact between the insulation and OSB boards by installing battens on the collar beams to create a minimum gap of around 5cm (2 inches) between the insulation and the OSB boards, to allow for ventilation. I have provisionally laid 6 boards this way to observe the situation.
What do you think of the construction company’s advice? Is it generally normal that this kind of condensation occurs as I described, or am I dealing with construction defects?
How would you address this issue to prevent moisture buildup and mold growth?
Thanks for some knowledgeable answers.
I have been browsing through various forums for several days but only found fragmented information that doesn’t quite match my problem.
On October 1st of this year, I moved into a newly built one-story L-shaped bungalow. Basically, everything is fine so far.
During the construction phase (when the ceiling was still open), I placed 40m² (430 sq ft) of OSB boards on two piles on the ceiling joists to later install them on the future "cold floor" after moving in.
After moving in, I laid some OSB boards in the attic as a walkway to access the roof and to place some boxes on. I placed these directly on the joists; contact between the boards and the insulation cannot be ruled out, as the insulation is almost flush with the joists.
The insulated ceiling structure from the living area side is as follows: 1. gypsum board, 2. aluminum profiles, 3. vapor retarder (blue foil), 4.+5. joists with 200mm (8 inches) insulation wool in between. The roof is uninsulated, essentially a cold attic; insulation is only in the floor ceiling.
Now, after about 9 weeks, I accidentally noticed that some of the boards are significantly wet on the underside (facing the insulation). It clearly looks like condensation. One of the boards already shows slight signs of mold.
My immediate action: I stood all the boards vertically to prevent further moisture buildup and to let the already wet boards dry out.
I have also called the construction company and explained the situation. They advised me to avoid contact between the insulation and OSB boards by installing battens on the collar beams to create a minimum gap of around 5cm (2 inches) between the insulation and the OSB boards, to allow for ventilation. I have provisionally laid 6 boards this way to observe the situation.
What do you think of the construction company’s advice? Is it generally normal that this kind of condensation occurs as I described, or am I dealing with construction defects?
How would you address this issue to prevent moisture buildup and mold growth?
Thanks for some knowledgeable answers.
E
Erbsenzähler707 Oct 2021 10:27Well,
my house has also been standing for quite a while. I am allowed to do that.
Regards
my house has also been standing for quite a while. I am allowed to do that.
Regards