Decentralized ventilation only in individual rooms in new construction KfW 55?

and what costs are supposed to be? Not even maintenance is needed for ventilation

At least for us, central systems were often always presented as mandatory when buying a house, often combined with maintenance contracts. Due to hygiene, possible mold and fungal infestation, etc. Without a maintenance contract, the warranty period is usually shortened anyway. When buying a house, we decided against such a system. Fresh air in the bathrooms, kitchen, and bedrooms would be nice, though. If so, only decentralized would be an option for us. Now I’m a bit hesitant because of the many necessary drillings into the building envelope. Also, I checked out a residential ventilation system from the company Inventer at the neighbors’ place and found it quite loud in operation. The neighbors have a prefabricated house with 24cm walls. We have 36cm monolithic masonry and are considering the Inventer Corner. Which decentralized fans are recommended? Preferably smart home and self-regulating.

At least for us, central systems were often always offered as mandatory when buying a house and often combined with maintenance contracts. Because of hygiene issues such as possible mold and fungal infestation, etc.

That is what is commonly called a scam.

Without a maintenance contract, the warranty period is usually shortened anyway.

You always get the statutory 2 years, which are generally sufficient. As many have already written here, there is hardly anything in it that can break.

When buying a house, we waived such a system. Fresh air in the bathrooms, kitchen, and bedrooms would be nice though.

Yes, that is the purpose of the system. But not only in selected rooms, rather throughout the entire building.

For us, only decentralized would be an option.

Hmm, well, better than nothing.

Now I hesitate a bit because of the many necessary drillings into the house envelope. Besides, I have looked at the residential ventilation from the company Inventer at the neighbors and found it quite loud in operation.

Yes, that's the nature of the matter. Smaller fans with the same air volume = higher speed = higher noise level and, of course, quicker wear.

The air volume remains the same whether central or decentralized; the rooms don't shrink or grow depending on which system you use.

Which decentralized fans are recommended? Preferably smart home self-regulating.

Honestly, none. But, for example, Lunos is quite well regarded. Of course, it also has pros and cons.

This is what is commonly called deceptive advertising.


You always get the legal 2 years which are usually sufficient. As many have already written here, there is hardly anything in there that can break.


Yes, that is also the purpose of the system. But not only in selected rooms, rather throughout the entire building.


Hmm well better than nothing.


Yes, that is the nature of the matter. Smaller fans with the same air volume = higher speed = higher noise level and of course faster wear.


The air volume remains the same whether central or decentralized, the rooms do not shrink and do not get bigger depending on which system you use.


Honestly. None. But for example, Lunos is quite well regarded. However, it also has pros and cons.

Thank you very much. I'll take a look at it.