Hello everyone,
We are currently starting to deal with the technical aspects of our single-family home.
I haven’t found a thread discussing whether a ventilation system generally makes sense or not. So here is a general discussion thread on the topic:
At first, we looked into various timber frame construction providers, which made us quite sensitive in this area. Naturally, a ventilation system is quite important due to the tighter building envelope, which I can completely understand. However, everything is also marketed accordingly...
Since we have now decided to go with a regional solid construction company, completely different questions arise:
I currently have a detailed offer from a solid construction company:
- $10,000 additional cost for thermal insulation measures
- $13,000 additional cost for a central ventilation system or $9,000 additional cost for a decentralized ventilation system
--> So the repayment subsidy of $18,000 is of little use to me; on the contrary, I am even paying extra for this (of course, I get a “better” house in return).
Key Data:
- Single-family home city villa, 150m² (1,615 ft²) with basement
- Air-to-water heat pump
- Building material: brick
The questions I am now asking myself:
1. Is a ventilation system even necessary to achieve KfW 55 standard?
2. If yes, would it maybe make more sense to go for KfW 70 and forget about the subsidy?
3. Is a ventilation system really that great? There are many reports about noise, high maintenance, etc.
4. If yes, in our building project would a decentralized or central system be better? I have read a lot of positive things about decentralized systems, so central ones might not be an option? Is that correct or not?
5. Is it even possible to reach KfW 55 standard otherwise? Do you really have to ventilate every 2 hours? Are there any experiences?
6. Is the additional $10,000 cost for KfW 55 without a ventilation system justified? Are the prices for the ventilation systems justified?
I know this is an endless debate and there are clearly two opinions here. However, we find it really difficult to make a decision. Maybe a few discussions and information here will help us make up our minds.
We are currently starting to deal with the technical aspects of our single-family home.
I haven’t found a thread discussing whether a ventilation system generally makes sense or not. So here is a general discussion thread on the topic:
At first, we looked into various timber frame construction providers, which made us quite sensitive in this area. Naturally, a ventilation system is quite important due to the tighter building envelope, which I can completely understand. However, everything is also marketed accordingly...
Since we have now decided to go with a regional solid construction company, completely different questions arise:
I currently have a detailed offer from a solid construction company:
- $10,000 additional cost for thermal insulation measures
- $13,000 additional cost for a central ventilation system or $9,000 additional cost for a decentralized ventilation system
--> So the repayment subsidy of $18,000 is of little use to me; on the contrary, I am even paying extra for this (of course, I get a “better” house in return).
Key Data:
- Single-family home city villa, 150m² (1,615 ft²) with basement
- Air-to-water heat pump
- Building material: brick
The questions I am now asking myself:
1. Is a ventilation system even necessary to achieve KfW 55 standard?
2. If yes, would it maybe make more sense to go for KfW 70 and forget about the subsidy?
3. Is a ventilation system really that great? There are many reports about noise, high maintenance, etc.
4. If yes, in our building project would a decentralized or central system be better? I have read a lot of positive things about decentralized systems, so central ones might not be an option? Is that correct or not?
5. Is it even possible to reach KfW 55 standard otherwise? Do you really have to ventilate every 2 hours? Are there any experiences?
6. Is the additional $10,000 cost for KfW 55 without a ventilation system justified? Are the prices for the ventilation systems justified?
I know this is an endless debate and there are clearly two opinions here. However, we find it really difficult to make a decision. Maybe a few discussions and information here will help us make up our minds.
AxelH. schrieb:
[...] humming and buzzing [...]Well, I’m currently sitting in a living room with two of these fans running on setting 2, and there’s no humming or buzzing here. The only sound I hear is the refrigerator “gurgling.” But it’s true, you can hear them in the bedroom in the evening. Even my wife got used to it pretty quickly.
Nairil schrieb:
But it's true, you can definitely hear them in the bedroom at night.And that's exactly why I wanted to—perhaps a bit exaggerated on purpose—to warn about possible disadvantages. In the planning phase of a house, you can still consider many options. Once the walls and floor are finished, only the decentralized option remains.AxelH. schrieb:
Isn’t this the same thread where you keep readingTrue... my mistake as a newbie – after all the posts, I assumed that a mechanical ventilation with heat recovery would automatically mean a central system :-D – it’s come to that here – some people should work for these ventilation system manufacturers, judging by how convincing they are 😀
pagoni2020 schrieb:
By the way, he told me on this topic that he is now leaning more towards decentralized ventilation systemsI would really like to know which decentralized ventilation system can be recommended with a “clear” conscience... Most likely, you have to see for yourself on site whether the noise level of the unit is acceptable.
Any recommendations would be appreciated, and NO – a central mechanical ventilation with heat recovery is not affordable.
P
pagoni202011 Apr 2021 21:31Hardi88 schrieb:
I would really like to know which decentralized ventilation system can be recommended with a "clear" conscience... First, I would clarify that with the specialist company responsible, since they will also be installing it.
I have not had either a central or decentralized system myself.
If I were you, I would start a separate thread here to ask for advice, then research information online, and finally, if possible, see such a system in operation in person.
Hardi88 schrieb:
Most likely, you have to see for yourself on site whether the noise level of the device is acceptable. Exactly.
The problem is that the environment varies and can’t be directly compared.
I think it’s similar to heat pumps for me. If you see the device and expect a humming noise, you will hear it. Your house will never be completely silent. I once stayed in a desert location where you could hear absolutely nothing, which was almost unsettling.
Hardi88 schrieb:
NO - a central mechanical ventilation with heat recovery system is financially not feasible. I understand that well, and there are many users here who live comfortably without mechanical ventilation with heat recovery.
Personally, I don’t believe that there are inferior mechanical ventilation systems, as I base this on the opinion of an architect I respect. Also, I wouldn’t want others here to spoil my experience with such systems. The more you focus on it, the more you’ll notice any noise!
Some people who are bothered by that might find a loud V12 engine in a car cool, or might be used to unnecessary, humming technical noise or constant background noise in daily life.
I’m not trying to downplay this, but I’m not a fan of black-and-white thinking or “this is the only way” approaches — that goes for mechanical ventilation as well. Most devices have some side effects, and these are usually accepted.
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