Is mold formation possible?

Hello everyone,

we have the following issue with our new building currently under construction, where our developer wants us to confirm that potential mold formation is possible:

we have a storage room, about 3m² in size, adjacent to the kitchen. This room is located at a corner of the house, so it has two exterior walls. There is also an exhaust pipe for our controlled residential ventilation system in the room; our house will be an Efficiency House 40.

We did not want underfloor heating in the room because we also wanted to store food there. However, during the sanitary installation, two loops from the kitchen were (accidentally) installed there.

The reasoning now is that the room cools down so much due to the two exterior walls that condensation can form and thus promote mold growth.

I find this hard to believe, because actually the room cannot cool down that much, as mentioned, highly insulated exterior wall and there are also two uninsulated interior walls (kitchen and guest WC) adjacent.

Is there really this problem?

Thank you all in advance :o)

We also have a pantry measuring about 2.5x1.8m at the corner exterior wall, where I have the underfloor heating turned off. The room probably feels around 18 degrees. Without it, it could definitely become critical with mold. Have the pipes laid and turn the heating down, and if mold ever appears, you have something to heat with. PS. What surprises me is that the doors insulate the heat so well.

The problem is that the chamber cannot be controlled separately from the kitchen, kitchen and chamber are a cycle...

ah okay controllable separately with us! but what I wonder is whether it is even allowed to operate a room in a thermal envelope without heating. but regarding your highly insulated exterior walls, what do you think why no water pipes run in the exterior wall? because it’s too cold. how much would it cost to install another heating circuit? or to separate the heating circuit with a valve from the kitchen.

The next problem is that the screed has already been laid by now and the whole thing would be somewhat more complicated. But maybe the valve would really be a viable compromise... :)

I think that is well done. We have a corner like that as a laundry room next to the bathroom, without heating. I have specially added a convector because otherwise it cools down quite a bit.