ᐅ Air-to-water heat pump or gas heating combined with controlled ventilation in a 135 sqm single-family home?

Received the answer today:

"The detailed energy saving ordinance calculation is not yet available. We have only received from the energy consultant the statement that you can forgo the solar system if you choose the controlled residential ventilation. Once the exact equipment and the construction plans are available, he can prepare his calculation in detail. I would be happy to share the key figures with you then. At the moment, however, this is still not possible. Thank you for your understanding."

M4rvin schrieb:
Received the answer today:

"The detailed energy performance calculation is not available yet. We have only received from the energy consultant the statement that you can forgo the solar system if you choose the controlled mechanical ventilation. Once the exact devices and the construction plans are available, he can prepare the detailed calculation. I can then share the key figures with you. Currently, this is not possible. Thank you for your understanding."

It's a pity, but thank you for the feedback.

I once entered our house into an energy performance calculator including all the U-values and so on, and the result was that the Ht-value was about 15% below the current energy regulation requirement, but the annual primary energy demand for the combination of gas plus controlled mechanical ventilation without solar did not reach 15% below the current regulation requirement (due to the compensatory measure for the Renewable Energy Heat Act).

On the contrary, only the combination of gas plus controlled mechanical ventilation plus solar achieved an almost exact result just below the permissible maximum annual primary energy demand. Therefore, in my opinion, the combination of better insulation and controlled mechanical ventilation without solar would not qualify as a compensatory measure under the Renewable Energy Heat Act. A blower-door test would improve the result even more, but still not reach 15% below the 2016 energy regulation standard building.

Let's see what our energy consultant says.

I now suspect that the benchmark for the numbers posted by Alex85 (Qp 55% and Ht 70%) is the reference building of the energy regulation and not the current 2016 version requirements of the energy regulation (Qp of the reference building × 0.75, Ht of the reference building × 1.0, so no tightening here).

In that case, 55% of the reference building would still be an excellent result.