ᐅ Air-to-water heat pump with centralized ventilation system?

Hello everyone,

I am a layperson to start with.
Therefore, I am trying to clarify some uncertain factors and am asking for advice in this forum.

I am building a semi-detached house with 160 m² (1,722 sq ft), without a basement, but with a 40 m² (430 sq ft) attic.
In addition, a air-to-water heat pump from Buderus with a hot water storage tank will be installed, along with underfloor heating on every floor with individual room controls.

Now I have a few questions:

1. How harmful is it to install the heating system in the attic instead of the usual/standard location in the basement?
Would it operate less efficiently due to the longer piping runs?

2. Our building permit / planning permission does not include a mechanical ventilation system, as it was calculated that natural ventilation will be sufficient for the semi-detached house in terms of indoor air quality.
What are your opinions on natural ventilation in new buildings?
Or should I invest in a centralized or decentralized mechanical ventilation system?
Is it possible to integrate this ventilation system cost-neutrally directly with the air-to-water heat pump?

I appreciate any advice and suggestions for improvement regarding the ventilation and heating system.

Best regards and MERRY CHRISTMAS

Whether the heating system is located on the ground floor or the upper floor will have relatively little impact on efficiency. More important for efficiency is a room-by-room heat load calculation based on the room temperatures you set. Although individual room control is required by regulation, you can remove it after the inspection and set the heating system to a fixed setting.

We are also building a semi-detached house, but with a converted attic, our living space is about 149 m² (1,605 sq ft).
An air-to-water heat pump and a mechanical ventilation system with heat recovery are also planned.
These will be installed in the attic to save space on the ground floor.
According to our architect and installer, this does not affect efficiency.

lin0r87 schrieb:

We are also building a semi-detached house, but with a converted attic we have about 149 sqm (1605 sq ft).
An air-to-water heat pump and a mechanical ventilation system with heat recovery are also planned.
This will be installed in the attic to save enough space on the ground floor.
According to our architect and installer, this does not affect efficiency.

Could you tell me the brand/model of your air-to-water heat pump?

How much did the ventilation system cost you?

Is it a central or decentralized ventilation system?
Thanks

1. Regardless of where the system is installed, the routing of the pipes remains basically the same. For basement installation, you need to run the pipes from the basement to the attic, and for attic installation, you need to run them down to the basement. In the attic, if it is an uninsulated roof (cold roof), you must ensure the system is adequately insulated or installed within a separately insulated area.

2. Natural ventilation is sufficient for any house, provided there is enough time to maintain the ventilation intervals. To achieve approximately 0.33 air changes per hour (minimum ventilation), windows would need to be fully opened for about 5 minutes every three hours — including during the night. In reality, ventilation is often much less frequent. As a result, air quality in new buildings without mechanical ventilation is affected.

- Central controlled residential ventilation systems are always preferable to decentralized units. It always depends on the situation.
- No combination can be cost-neutral. Anything additional you want will also cost extra.

However, I would not want to live in a modern house without controlled residential ventilation. It comes with too many disadvantages.