KFW70 with gas-solar heating

Exterior masonry according to Kfw 85:
- 17.5 cm aerated concrete
- Thermal insulation mat made of mineral fibers according to Wärmeschutznachweis at least 14 cm (WLG 0.35)
- 11.5 cm facing brick

For an additional charge of €2,000, the following upgrades are available:
- 140 mm core insulation WLZ 0.035 in the facing masonry
- 180 mm mineral wool insulation WLZ 0.035 in the rafter area
- 240 mm mineral wool insulation WLZ 0.035 in the collar beam area
- 100 mm polystyrene rigid foam insulation WLZ 0.035 under the ground floor screed

In addition, there is the solar system for water heating.

This would then make Kfw 70 possible.
The surveyor, of course, costs around €500 extra.

Nothing changes with the masonry, right? Roof insulation and so on are also hard to assess without a comparison. What do you have under the screed otherwise? 8 cm? What about the windows? Ug, Uf?

For us, the KfW70 standard is supposed to cost an additional 7,000 EUR. In return, we then get thicker/better insulation.

I actually thought that the following things already achieve KfW70. We have:
- 24.5 cm Poroton + 12 cm VMS (insulation) + 2 cm exterior plaster
- Triple-glazed insulating glass
- Solar system for domestic hot water preparation including 300 l storage tank

What would have to be different in order to achieve KfW70?

For 7,000 EUR it surely hardly makes sense, right!?

Why is solar thermal energy already included by default when KfW70 can only be achieved through additional insulation? Then 7000€? That is the cost of the solar system, but not the insulation!

I also find it very strange. I only received the statement: "For KfW 70, your house will be additionally insulated." Unfortunately, I have (so far) not received any information about what the insulation would look like.

The solar thermal system is definitely already included in the standard and costs nothing extra.

Solar thermal energy is definitely already included as standard and does not cost anything extra.

Hello,

solar thermal energy is probably already included because since 2009 a certain share of the building's energy demand must be covered by renewable energy sources.

Therefore, most buildings heated with gas now have these (usually 2) solar thermal collectors on the roof.

Regards,

Dirk