Which wall structure is meaningfully vapor-permeable?

About the trickle vents: they are (too) cheap. Selling a controlled residential ventilation system brings more profit. They are theoretically non-energetic, in practice it is hardly noticeable: 46,- euros gas per month. It is often the case on the customer side in Germany as well that we do not want the simple solution (vaccination in centers instead of in supermarkets, cars with 1000 assistance systems instead of speed limits, among other things).

Choose a building material that appeals to you and then find a company that is familiar with it. This way you will get the best result. Whether stone, concrete, timber frame construction (OSB or plywood), CLT/BSP is then just a matter of taste, everything has its advantages and disadvantages, and you can build a wonderful single-family house out of any of them.

Ok yes that

About the rebate ventilators: they are (too) cheap. Selling a controlled residential ventilation system brings more profit. They are theoretically energy-neutral, practically you can hardly notice it: 46 euros gas per month. It is also often the case on the customer side in Germany that we do not want the simple solution (vaccination in centers instead of supermarkets, cars with 1000 assistance systems instead of speed limits, among other things).

That makes sense to me. I am curious how the general contractors will react to this topic. Regarding manual ventilation, I have to say that especially in winter, when it is most important, we do it the least. Normally, windows should be aired out by shock ventilation 3-5 times daily. Unfortunately, I don’t find it the optimal solution in 2021 to open all windows wide at -10 degrees. I can do this temporarily if something is broken, but if I am building a house, I want to avoid exactly what already annoys me now. Additionally, the windows are always decorated around Christmas, which additionally complicates fully opening them. Actually, I find the solution with rebate ventilators very suitable. Are there specific requirements for the building if you want decentralized or UKWL?

We ventilate in the morning after getting up, when we come home, and before we go to sleep. This is not rocket science and always makes the air smell nice and fresh.

Are there specific conditions on the building if you want decentralized or UKWL?

No, you just have to meet the overall minimum energy requirements. But it's not rocket science and you personally don't have to do it either. P.S. For me personally, window rebate ventilators are at most something for refurbishment or rental properties. In new buildings, always a controlled ventilation system, which is significantly better in terms of energy and also controllable/regulatable.

We air out in the morning after getting up, when we come home, and before we go to bed. It's not rocket science and always makes the air smell nice and fresh.

Indeed, it’s not rocket science, but: opening the windows in the evening on two floors in all kinds of weather is not an option for me in a new building. There are also days when it rains heavily (especially here) or there are strong winds. Then you always have to secure the windows and doors so they don’t slam open and shut. For one person it’s no problem; for me it’s annoying and I want to avoid that in a new house. I have nothing against occasional airing out, but anything that becomes a duty turns into work, and anything that becomes work is annoying ;)