District heating vs air-water heat pump in KfW 40 plus

Hello everyone,

we are currently planning our single-family house (approx. 160 m^2). It will be built with a timber frame construction and a basement. The prefab house provider offers a KFW 55 house as standard. The rooms will be heated with underfloor heating.

In the building area, connection to the local district heating network is mandatory, unless you build a Kfw 40 plus house.

I have compared the possible costs.

District heating:
District heating connection including transfer station €8,948.80 (offer)
Additional heating circuit for underfloor heating €952.00 (offer)
Hot water storage tank €1,000.00 (estimate)
Connection costs "heating" €3,000.00 (estimate)

Basic price per year: approx. €350
Price per kWh 10 cents gross

Total €13,900.80

Upgrade to KfW 40 plus:
Additional insulation of the house wall €5,590.00 (offer)
Photovoltaic system €5,590.00 (offer)
Electricity storage €7,990.00 (offer)
Air-water heat pump €3,000.00 -> offset with current planning (estimate)
Additional insulation basement: €2,000.00 (estimate)

Total €24,170.00
less KfW 40 plus subsidy €10,000

Adjusted total €14,170

I must admit that the conversation with the energy consultant is still pending. They will probably be able to say exactly which measures are necessary to achieve the KfW 40 plus standard.

Would you pursue this topic further or is KfW 40 plus with a basement unattainable? Initially using the available district heating and then switching after 10 years is probably not sensible either?

Thank you very much for your feedback!

Best regards
Björn

The repayment grant for KfW40plus is 15,000€. For KfW40, the repayment grant is 10,000€. Unless it is the difference between the repayment grant of KfW55 and KfW40plus.

I will build a timber frame house with a basement myself, which will achieve KfW40. However, not 40plus, because currently the battery storage systems are uneconomical for me. However, if I had been forced to use a local heating connection, I would certainly have chosen the KfW40plus option. You are somewhat more independent there. Even if you do not know how electricity prices will develop. But with local heating, you are tied to one provider. And at the same time, you have a better insulated house.

Is a ventilation system with heat recovery included in the offer for the KfW55 house? It is required for KfW40 and KfW40plus.

This is my layman’s opinion, the energy consultant will surely be able to explain in more detail how the ongoing heating costs differ.

the repayment grant for KfW40plus is €15,000. For KfW40 it is €10,000. Unless it is the difference between the repayment grant of KfW55 and KfW40plus.

It is the difference between KfW 55 and KfW 40 plus.

The offer for the KfW 55 house already includes a ventilation system with heat recovery. The basement insulation is currently 14 cm.

Of course, you also have to consider that the additional costs must be covered from equity if the loan agreement has already been finalized.

Are there any KfW 40 plus homeowners here in the forum?

Local heating sounds quite unattractive. The investment costs are not insignificant, you are bound; the annual basic price is outrageously high and the kWh prices are also high. An air-to-water heat pump achieves one kWh of heat for comparable costs (with a COP of 3 you are under 10 cents at the current electricity price). You could also simply use it in a KFW55 house otherwise and that would make the total price much lower than with local heating.

I have now received more precise figures:

District heating
Basic price (for the first 15 kW) €401.57
Basic work price 10.12 ct/kWh

The problem is simply that in the standard case of "district heating" I am not allowed to install another heat source in the house. Only in a KfW 40 plus house would I be exempt. On the other hand, the technology in my house with district heating is quite manageable. From my point of view, less can go wrong there and maintenance is at least included in the price.

In a KfW 40 plus house, I would have the photovoltaic system, the air-to-water heat pump and the battery storage to maintain and care for. The battery storage still has room for improvement.

I am torn back and forth, but the home builder should simply calculate it.

Hello,

I have now received more precise figures:

District heating
Basic price (for the first 15 kW) €401.57
Basic work price 10.12 ct/kWh

The problem is simply that in the standard case of "district heating" I am not allowed to install any other heat source in the house.

the price is more than just outrageous. By comparison: we currently consume about €400 per year in gas for a gas heating system for 135 sqm plus 60 sqm of heated basement. So that’s what they want to charge you as a basic price...
And then you are completely at their mercy; you can’t even change the provider like you can with the electricity provider for a heat pump.

and the second restriction is naturally intended to secure the provider’s future business.

That would be an absolute no-go for me.

Best regards,

Andreas