KFW 70 House - new law

Hello experts,

I have now been to 4 developers and one developer says that a Kfw 70 house, which was certified last year with an air-water heat pump, now also needs a solar system in addition. Can anyone confirm this because I can't find anything at Kfw.

Do I now need a solar system for a Kfw 70 house in addition to my air-water heat pump or can I leave it out? We are building a city villa and a solar system on the roof doesn’t bring much and also costs a lot.

Thank you very much for your answers.

Regards

Jayden

Hello experts,

I have now been to 4 developers and one developer says that a KFW 70 house, which was certified last year with an air-water heat pump, now also additionally needs a solar system. Can anyone confirm this because I can't find anything with KFW.

Do I now need a solar system in addition to my air-water heat pump for a KFW 70 house or can I leave it out? We are building a city villa and a solar system on the roof doesn't bring much and also costs a lot.

Thank you very much for your answers.

Regards

Jayden

I would be interested too. My developer has included the solar system optionally in the building description in case the measures are not sufficient!

The strange thing is that the other three developers said nothing about the same requirement. Is KFW enforced so strictly or is there still some leeway?

The KFW does not prescribe a single measure, but has created a "model house." From the energy demand of this KFW model house, the corresponding KFW standards are then calculated. It is also required that a certain portion of the energy must be generated using renewable energy. Therefore, a solar system is usually necessary with a gas condensing boiler. An exception is the 15% rule, where better insulation can circumvent this. With heat pumps, a solar system is actually not necessary.

What I can imagine is that the insulation varies among the 4 developers and that the solar system is used to "balance" this out again. Actually, a townhouse is much better in terms of energy consumption from the building envelope than, for example, a bungalow. The townhouse offers a lot of area/volume with low exterior surfaces and thus less energy loss through the exterior walls and the ceiling. If, of course, many bay windows are added, the exterior surface and thus the heat loss increase. This may, under certain circumstances, make an additional measure necessary.

Hello,

I have now been to 4 developers and one developer says that a KFW 70 house, which was certified last year with an air-water heat pump, now also additionally needs a solar system. Can anyone confirm this because I can't find anything with KFW.

Do I now need a solar system in addition to my air-water heat pump for a KFW 70 house or can I leave it out. We are building a townhouse and a solar system on the roof doesn't bring much and also costs a lot.

I would rather suspect that the additional solar system for domestic hot water heating is the anticipatory compliance with the Energy Saving Ordinance 2014 ... if it is actually adopted in 2014. You probably still want to sign the building contract this year, so the Energy Saving Ordinance 2009 applies to you - as to everyone else.

Regards from the Rhineland