House construction, KFW70, approx. 150m², which heating? Gas/air-water heat pump?

So the decentralized system is probably cheaper. But since we started looking at houses, I have always disliked having these holes in the wall -. - and those ugly caps that go with them. The central system is then probably more expensive; with our provider, the Vaillant recoVair is currently on the negotiation table. Regarding efficiency or performance, I haven’t read in the other forum whether the "hole in the wall, decentralized" differs from the "machine in the utility room and pipes in the house to every room, central" system.

By the way, here are my questions about the "wall structure and insulation"

As with the type of heating, ventilation also depends on your budget and is furthermore a matter of belief.

It is important that you inform yourself well. In the end, your gut feeling will surely decide.

a) do you live loudly or quietly? -> loud: central, quiet: central/decentralized
b) is money very tight? -> no: central, yes: decentralized (tends to be somewhat cheaper)
c) are you afraid of the bad pipe? -> no: central/decentralized, yes: decentralized
d) do you possibly want to rent out a floor? -> no: central/decentralized, yes: rather decentralized (otherwise you argue about drafts - although you can possibly reduce outlets?!
e) do you value the appearance? -> yes: central, no: central/decentralized
f) are you very noise sensitive? -> yes: central, no: decentralized/central
g) does your BU/GÜ pressure you to any solution? -> take the one, he can’t/doesn’t like the other one

-> This nice little list could almost be pinned somewhere as a decision aid for ventilation systems in a separate top post? I think it fits quite well!

Clean ... and what happens during the extraction of the gas?

If you go by that, you would have to build a passive house. Electricity is not exactly ecological either, and the production of heating systems is certainly not ecological at all... But sure, topics like fracking etc. are not great and argue against gas.

But economically speaking, the acquisition costs for gas (or sometimes still for an air heat pump) are the cheapest. And even if you have e.g. 300 euros more heating costs per year, that's still "only" 6,000 euros more over 20 years. And I would say, for example, that a ground source heat pump with trench collectors easily costs over 6,000 more than a gas boiler.

a) do you live noisy or quiet? -> noisy: central, quiet: central/decentralized
b) is money very tight? -> no: central, yes: decentralized (tends to be somewhat cheaper)
c) are you afraid of the evil pipe? -> no: central/decentralized, yes: decentralized
d) do you possibly want to rent out a floor? -> no: central / decentralized, yes: rather decentralized (otherwise you argue that there is a draft - although you might also reduce outlets ?!
e) do you value the appearance -> yes: central, no: central / decentralized
f) are you very noise-sensitive? -> yes: central, no: decentralized/central
g) does your BU/GÜ pressure you into any solution? -> take the one, he can’t/doesn’t want the other

Whereas I would add to e) that visible pipework in the rooms would also not appeal to me visually (I know - there are also systems where the pipes are routed differently).

-> This nice small list could almost be pinned somewhere at the top in a separate post as a decision aid for ventilation systems? I think it fits quite well!

I think the suggestion is good. Maybe the mods can arrange something.

But economically speaking, the purchase costs for gas (or partly still for an air heat pump) are the cheapest. And even if you have, for example, 300 euros more heating costs per year, that’s still “only” 6,000 euros additional costs in 20 years. And I would say that, for example, a ground source heat pump with trench collectors easily costs over 6,000 more than a gas boiler.

Well - we paid all in about 14 - 15 thousand euros for the geothermal system.
With gas, you still have to plan for connection costs as well as the annual chimney sweep. In addition, you really can’t estimate the development of gas prices - but this also applies to electricity prices.

Well - we paid about 14 - 15 TEUR in total for geothermal energy.
With gas, you still have to plan for connection costs as well as the annual chimney sweep. In addition, the development of gas prices cannot really be estimated - but this also applies to electricity prices.

That is little.
Geothermal energy would have been our next choice after gas. However, the costs would have been significantly higher: Drilling about €10,000 plus heating with nearly €12,000, plus the appropriate building envelope: additional costs of nearly €13,000.
Our gas heating system with solar support and a 210 l hot water storage tank including a 60 m supply trench and house connection cost just under €6,000.

Our considerations: For €29,000 we can heat for a long time and pay the chimney sweep €45 once a year.

If our gas heating system needs to be renewed in 8-10 years, we could switch to a different system. We have already created the prerequisites for this by the close installation of the underfloor heating.