Does mold go away by insulation or not?

I understand the fear of mold and believe that the problem should be taken seriously.

Panicked reactions often don't improve anything, so: "stay calm," but "mold is no joke." It won't turn into a disaster that quickly, but it requires care.

My wife has asthma caused by exposure because she lived with mold undetected for a long time. You can live with it, but if you can avoid it, of course, that's better.

I myself - without being an expert - have in mind that mold is not easy to eliminate - and would first try to find a "professional" who can look at it on site and whom I can trust. In my assessment, such a person is needed because the matter is complex.

I wish you all the best! :-)

21 degrees and 60-75% relative humidity indicate improper ventilation.

Whereas, as we are currently noticing, with the current temperatures it is simply great to ventilate moisture out of the house. For example, the other days it was around 0°C and foggy here (so relative humidity outside about 100%). Because of the fog, we were initially afraid of bringing moisture into the house through ventilation, but then we calculated it and the air outside was simply still significantly drier. (0°C and 100% relative humidity corresponds to 4.85 g/m^3, which when heated to 20°C is only about ~28% relative humidity). Of course, it still takes time for the moisture to come out of the walls, and yes, the prerequisite is that heating is on. But I find it currently much easier to get moisture out of the house than, for example, on rainy days in autumn.

first of all, I wish you a happy new year! Lots of health, success, and above all no problems with your property :-)

Thank you very much, I wish you the same!

I have read that cabinets should not be placed too close to the exterior wall so that the air can circulate. Today we first sprayed all affected spots on the walls with mold remover, opened all windows, and left the house for three hours

Both are already very good as first aid measures or to improve air circulation.

But my husband says that everything gets better with insulation.

I agree with your husband! After our renovation (old building from 1912, among other things new tighter windows), we also had mold on exterior walls in the first winter; what helped was removing/treating mold, heating more consistently, and ventilating more often; additionally, monitoring humidity with a hygrometer and ventilating/turning up the thermostat when needed (even if that hurts in terms of energy saving). The following summer we had proper insulation installed, and since then we no longer have to heat “excessively”; we ventilate normally in the morning manually by cross-ventilation. Today I would also consider an automatic ventilation system; unfortunately, we had to unexpectedly finance the insulation expensively at that time (in addition to the ongoing mortgage). Due to the exterior insulation, the living climate in the second winter was much more pleasant than before; you find lower temperatures sufficient and do not have that unpleasant feeling of sitting next to a cold wall. Since then, there has been no more mold; so it is nothing that cannot be brought under control.

Hello everyone,

thank you very much for your replies!

Would you approach it the way I described above?

So: fight the mold this winter with remover, accept it meanwhile, and then insulate starting in summer and wait to see if mold appears again next winter?

Attached you will find the floor plan of our house. The two walls between the living/dining room and the kitchen, which we removed, are marked in red.

I would be interested to know exactly where in the house such decentralized fans should be best installed and which models you can recommend.

Does it make sense not only to ventilate briefly, but to keep the windows tilted open in two rooms to create a draft? Of course, this would only happen when we are not at home, for example while we are working.

Thank you in advance for your opinions and tips!



Best regards

Is this a possible way to implement the ventilation concept?

So: fight the mold this winter with remover, live with it, and then insulate starting in summer and wait to see if mold appears again next winter?

Additionally, turn up the heating and ventilate as much as possible. It does cost €, but with that you can get the mold under control after treating it with the remover. Buy a used portable air conditioner (with drying function) from the book and dry out the place. Costs about a hundred.

Does it make sense to ventilate not only in bursts, but to leave the windows tilted in two rooms to create a draft?

A draft is sufficient with the windows fully open for 3-5 minutes. Then the air is definitely exchanged. If you’re not at home, no new moist air gets into the place.

Is this a possibility to implement the ventilation concept?

Yes, with a central system. Decentralized makes no sense this way because there are no pure supply and pure exhaust rooms. Unless you forgo heat recovery. But then you might as well keep the windows tilted and air out the warm air.
I would probably install five decentralized units. Living, cooking, sleeping, bathroom (maybe just a humidity-controlled exhaust fan here), child’s room. Possibly one unit is enough for kitchen/living, if it has a bit more capacity.

Once the insulation is installed, it’s more about getting basic ventilation. If the humidity is still too high in autumn despite the fans, you can simply fight against it for a few days with the air conditioner and pull moisture out of the rooms.