New single-family house, gas or heat pump, target KfW55

Hello,

so what I am still wondering is how you can install a gas condensing boiler system with a solar thermal system or the heat pump solution for the same money. Either the system with the gas condensing boiler is rather expensive or the heat pump solution is really cheap. Because usually the gas condensing boiler is the cheapest heating option to purchase. The heat pump, on the other hand, has the advantage that the often significantly higher investment costs are offset by the lower operating costs over a relatively long observation period, if, as Euro also suggests, a total investment calculation is made.
If you now get a heat pump system for the same money and with the same performance, then it would certainly be worth examining which operating costs you can expect in order to then make the economical decision for a system according to a total cost calculation.
On the other hand, if gas is already available on site, then the otherwise usual additional costs for gas condensing boilers should be limited.
Since you have already spoken of an economical decision, I would really recommend the comparison calculation to you.

Best regards

You forgot the controlled residential ventilation with the GT, which is already integrated in the heat pump system. Therefore, the same price applies.

.... Because usually the gas condensing boiler system is the cheapest heating option to purchase....

That should be put into perspective, because the investment for an air heat pump and gas condensing boiler + connection costs are usually on par with the same performance! With gas, you can cook, with an air heat pump, you can cool! ;-)

.... Since you have already spoken of an economic decision, I would really recommend you to do the comparative calculation.

Correct, everyone should do that. However, knowledge of the actual energy demand for heating and hot water is required for this.

Best regards

Do you have an approximate idea of what heating load you need, what your climatic conditions are, etc. 230m² can have about 5kW as a passive house or so, as a normal house 25kW, maybe somewhere at 1500m above sea level and very long heating periods correspondingly even more.

Best regards, we would like to build a detached single-family house, solid construction, 230 sqm, Ytong or precast walls made of Bläton.

Do you have an approximate idea of what heating load you need, what your climatic conditions are, etc. 230 sqm can have about 5 kW as a passive house or 25 kW as a normal house, maybe somewhere around 1500m altitude and very long heating periods accordingly even more.

ok, massive is clear, but which insulation do you use and so on.
but basically it’s always a matter of feeling:
If you have your own forest and can accommodate it space-wise, you can install a wood chip system or wood gasifier with some solar collectors.
If you have the possibility of a gas connection at the property, a gas condensing boiler can make good sense.
If groundwater is accessible, you can install a groundwater heat pump. Deep heat pumps work almost always, with a sufficiently large plot, a surface/ditch collector is also possible.
I would generally only do an air heat pump with photovoltaic support and very good energy technical values.
Price-wise, a surface brine heat pump and an air heat pump are about the same. Deep drilling is more expensive and cannot be done everywhere.
In my opinion, a gas boiler only makes sense if there is a connection possibility near the property; an external tank and so on is rather pointless.

The less heating power you need, the cheaper it is, no matter which system you have, since a heating system with less power costs less to purchase (always compared the same with the same) and has lower running costs.
A gas condensing boiler with 14 kW nominal power costs about €1700 on Amazon, a heat pump with the same power costs about €10,000 (although drilling or excavation costs are added), an air heat pump about €13,000. Buffers and so on are not included, they are extra.
The 9 kW split air heat pump including all accessories (hot water buffer, separation tank, heating rod...), which we install, has a list price of €20,007. but these are all material costs only.

I hope you now understand a bit better that it is not easy to choose the right concept with the right provider and that there is no "jack of all trades." Every system on the market is designed for a specific application. Heat pumps make sense where supply temperatures are low (surface heating).

Somehow, I personally have the feeling that you have no idea at all what is available on the market and what could fit. Therefore, I would strongly recommend a "conversation" with former builders in your circle of friends and possible installation companies to get yourself up to date.