New construction Poroton T7 MW 36.5 without controlled residential ventilation

I say that because I am currently getting to know a lot of builders.

You are, after all — by virtue of your training — a clever guy ...?

**Just from concrete, mortar, plaster, and screed, between 10,000 to 20,000 liters of water are brought into a single-family home. That water must be removed, otherwise it becomes a problem. The solution in new construction is therefore above all systematic ventilation and drying — and preferably within the first four years after construction.

I took the liberty of citing the source, since I am often accused of bias

If you can only ventilate properly once a day, a controlled residential ventilation system is indispensable; depending on which KfW standard you want to achieve, also with heat recovery. The ventilation does not replace the required shock ventilation 1 : 1 — depending on the outside temperature, but it helps immensely to transport the moisture inside the house outside.

From my point of view, a controlled residential ventilation system is less about amortization and more about a necessary evil in times of built thermos flasks

**Source: Zuhause wohnen

Hello,

I have always seen it the same way as Bauexperte and Ypg and it still makes sense to me. However, when you talk to the different construction companies, I absolutely agree with Goldi09111. This is currently probably not a big issue (apart from prefabricated houses with vapor barriers), and then you start to wonder...

Therefore, a question to the group:
- What is the reason for this? Is it simply the extra investment that most builders want to save, or is it not as bad as it is sometimes claimed? After all, there is no actual vapor barrier, so the house can at least breathe a little, right?

- What would a proper controlled residential ventilation system with heat recovery cost me for ~170 sqm house? Or are there any recommendations or things to watch out for?

- What is the reason for this? Is it simply the additional investment that most builders want to avoid, or is it not nearly as bad as is sometimes claimed?

It is assumed that every second new building is affected by mold. So I would want to guess that it is a mix of two things: the builders do not want to make their houses even more expensive and the builders save the sensible investment because they like to believe the statements "you don’t need that".

- How much would a proper controlled residential ventilation system with heat recovery cost me for a ~170sqm house?

Approximately from EUR 12,000 and upwards, depending on the provider and including installation.

Rhineland regards

I think it would be more sensible to invest the 12k now instead of realizing after 3 years that the living quality is "ruined" because there is not enough ventilation.

Well, let's see what the ventilation system person offers us.

I am also in favor of controlled residential ventilation. You are spared from mold (and if you ever have it, you are ready to give a lot to get rid of it), the air always smells good (also in the morning in the bedroom, or after big parties, bathroom ventilation, etc.). I would have installed it myself if it had not been recognized as a "measure."

Today only with controlled residential ventilation.

Houses built today are so airtight that no 'air exchange' takes place anymore. And the thing with the breathing house is simply nonsense. There are building materials/stones that have a certain moisture regulation. They absorb moisture when the humidity is high and release it again when it decreases. However, it can only decrease if there is ventilation. If the indoor air is not exchanged, the indoor humidity continuously increases because there is no air exchange. Eventually, mold will develop.

That is why you should always plan for controlled residential ventilation today. If you want to reduce the investment, you can also consider a decentralized solution with heat recovery. It is cheaper but somewhat less efficient.

I have a central system with the pipes in the ceiling.