ᐅ KfW 70 House – New Regulation

Hello experts,

I’ve visited four builders so far, and one of them says that a KfW 70 house, which was certified last year with an air-to-water heat pump, now also requires a solar system. Can anyone confirm this? I couldn’t find any information about it on the KfW guidelines.

Do I need to add a solar system to my air-to-water heat pump for a KfW 70 house, or can I skip it? We are building an urban villa, and installing solar panels on the roof doesn’t seem very effective and is also quite expensive.

Thank you very much for your answers.

Best regards

Jayden

jayden1977 schrieb:
Hello experts,

I have visited 4 developers, and one of them said that a KFW 70 house, which was certified last year with an air-to-water heat pump, now also requires a solar system. Can anyone confirm this? I couldn’t find anything about it from KFW.

Do I now need a solar system in addition to my air-to-water heat pump for a KFW 70 house, or can I skip it? We are building a town villa, and a solar system on the roof doesn’t add much benefit and is quite expensive.

Thank you very much for your answers.

Regards

Jayden

I’m also interested in this. My developer included the solar system as an optional item in the building specification, in case the measures are not sufficient!

The strange thing is that the other three developers did not mention anything about this with the same requirement. Is KfW applied so strictly, or is there some flexibility?

The KfW does not specify individual measures but has created a "model house."
The energy demand of this KfW model house is then used to calculate the corresponding KfW standards.
In addition, it is required that a certain portion of the energy must be generated from renewable sources.
Therefore, a solar system is usually necessary when using a gas condensing boiler. An exception is the 15% rule, which can be bypassed with better insulation. For heat pumps, a solar system is generally not necessary.

What I can imagine is that the insulation varies among the four builders, and the solar system compensates for that in the calculations.
From a construction standpoint, a townhouse is much better in terms of energy consumption than, for example, a bungalow. A townhouse offers a large volume-to-surface ratio with reduced exterior surface area, resulting in less energy loss through the outer walls and roof.
However, if many bay windows are added, the exterior surface area increases, along with heat loss. This could make additional measures necessary.

Hello,

jayden1977 schrieb:

I have now been to 4 developers, and one of them says that a KfW 70 house, which was certified last year with an air-to-water heat pump, now also requires a solar system. Can anyone confirm this? Because I can’t find anything about it on KfW.

Do I need to add a solar system to my air-to-water heat pump for a KfW 70 house, or can I skip it? We are building a city villa, and a solar system on the roof doesn’t bring much benefit and also costs a lot.

I would rather suspect that the additional solar system for domestic hot water heating is a preemptive compliance with the 2014 Energy Saving Ordinance... if it is actually passed in 2014. You presumably want to sign the construction contract this year, so the 2009 Energy Saving Ordinance applies to you, just like everyone else.

Regards, Bauexperte