Which heating concept for new construction without ventilation system?

What arguments speak in favor of the ventilation system?

In short: An optimal indoor air quality (CO2, humidity, other odors and microorganisms) can practically only be ensured efficiently, permanently and comfortably through mechanical ventilation in current building standards.

if cost-effectiveness is important to you, I would look towards a gas heating system in your place.

That has to be considered ... With a creative energy consultant, the following should be examined:
- Gas heating with controlled residential ventilation (for energy saving ordinance), but without solar thermal versus
- Heat pump with controlled residential ventilation (for comfort)
Otherwise gas + solar thermal versus heat pump without solar thermal. For us, gas would have resulted in higher investment costs, which will also be the case in many other instances.

With gas, solar and controlled residential ventilation with heat recovery, you are already close to KFW55.

I doubt that, well, depending on what close means.

If the components of the thermal envelope also meet the reference values, then the matter is settled. Or did I misunderstand that?

What we have realized so far - if it has to be gas, it means multiple times the insulation. Otherwise, the energy saving ordinance cannot be implemented with gas; KFW 55 even less so. In total, an air-water heat pump is more cost-effective, especially since it also saves the gas connection. Rhineland regards

How is the reference value method to be understood then? Is that then a "loophole" to not completely ban gas from new buildings, if you can't gain anything with another calculation method?

How is the reference value method to be understood then? Is it then a "loophole" to not completely ban gas from new buildings, if you can't gain anything with another calculation method?

I have long since not understood the girls and boys who come up with such nonsense. The undisputed fact is only that gas is undesirable as a heat generator in the medium term (short term in new buildings). Rhine regards

The only undisputed fact is that gas is undesirable as a heat generator in the medium term (short term in new construction).

...and makes one independent from the Russian. *conspiracytheoryoff*

For KFW55, certain requirements regarding transmission heat loss and primary energy demand must be met. The transmission heat loss is completely independent of the technology. The primary energy demand is based on the reference building, which is heated with gas.

The fulfillment of the primary energy demand depends on the transmission heat loss. If this is just met, then the technology must be 21.4% (1 minus (55 divided by 70)) better than in the reference building.

Since the KFW55 insulation is already quite good, the majority of the heat demand in the reference building is ventilation-related. If a controlled residential ventilation system is used there, then the 21.4% is easily achieved.