Is an HRB possible without an installation level?

Hello friends of house building,

I am new to this forum and have just spent a few hours reading various threads here. My wife and I live in Berlin and are currently planning the construction of a small residential house (80m2 living space) in Brandenburg. The plot is available, the architect is planning, the structural engineer will join soon... We are optimistic!

The house is to be built as cheaply as possible and will basically be used only as a second home. We favor a timber frame construction. My two questions about that are:

— Is it conceivable to build a timber frame house without a INSTALLATIONSEBENE? That inevitably means that all sockets are surface-mounted? The cables running inside then each pierce through the vapor barrier, right? And with every picture you hang on the wall, with every fastening, etc., you inevitably penetrate the vapor barrier with screws / plugs? Cost-wise, dispensing with the installation level makes sense at first glance, but is that only a short-term view and does it backfire due to damage sooner than we can think?

— What does it mean for the LÜFTUNG if, as mentioned, we only live in the house part-time? If we sometimes are away for weeks and cannot ventilate, is a controlled residential ventilation system advisable or even necessary? Or can it be solved differently?

I look forward to your feedback and tips (and please bear with me as I enthusiastically familiarize myself with these many complex topics around the house).

Best regards from Berlin,
Erwin

Hi

Without installation level, in my opinion, it doesn't make sense. The possible sources of error are too numerous. But that could then save the controlled residential ventilation. I would also argue that it doesn't make sense cost-wise, since additional insulation is also being installed. A small controlled residential ventilation designed according to DIN makes sense.

Olli

— What does it mean for the VENTILATION if, as mentioned, we only occupy the house part-time? If we are sometimes away for weeks and cannot ventilate, is controlled residential ventilation advisable or even necessary? Or can it be solved differently?

If you are not there, no/less moisture accumulates, so ventilation is not strictly necessary. However, I would still plan for slight forced ventilation. For a small house, few rooms, or open floor plan, decentralized units are suitable, for example, which are not overly expensive. It also does not have to be for all rooms. Ventilation without heat recovery is not so popular anymore but could be suitable here – window rebate ventilators, central exhaust and supply air vents, or similar. Near Berlin, there is a ventilation office where you can listen to various decentralized devices with heat recovery and get advice. If you are planning a gas heating system, you might possibly avoid the less sensible solar thermal system by using a ventilation system (with heat recovery), if the energy saving ordinance calculator allows it. I myself still have a small rental apartment that sometimes stands empty for a longer time. I would really wish for ventilation there. People still shower, cook, etc., before leaving you should ventilate properly, which is not always possible, and the moisture remains. In the small airtight apartment, this is borderline. When you come back, the windows have to be thrown wide open.

If you are planning a gas heating system, you might be able to avoid the less meaningful solar thermal system with a ventilation system (with heat recovery), if the energy saving ordinance calculator manages that.

Thank you very much for the feedback, ! Could you please explain this part a bit more precisely? And name the ventilation office near Berlin? Thank you very much and best regards, Erwin

The possible sources of error are too numerous. But that could then save the controlled residential ventilation.

Hey , thanks for your feedback and explanation. I understand the connection between the installation level and sources of error – which exactly do you see there, and how do you mean that you could save the controlled residential ventilation as a result? Thank you very much and best regards, Erwin

Gas heating alone is no longer permitted according to the Energy Saving Ordinance. Typically, solar thermal systems are installed together with gas for domestic hot water generation as the most cost-effective option. Without this requirement, solar thermal is not economical; I would exchange it for something more useful. There are house providers that offer their standard houses with controlled residential ventilation and gas, without solar thermal. From what is read in forums, most energy consultants or energy saving ordinance certifiers have difficulties with this. It is possible, but it also depends on the rest of the house. For KFW 55, for example, gas and controlled residential ventilation alone are not sufficient as far as I know.

And name the ventilation office near Berlin?

Please search briefly on the internet, I do not want to advertise here.

Installation level and sources of error – which exactly do you see there, and what do you mean that one could save the controlled residential ventilation because of this?

If the building envelope is leaky, you do not need forced ventilation.