Is an energy consultant necessary for KfW55?

Some people really make a science out of it. I checked again with us, we are talking about 2,300 euros net for the all-inclusive package. As mentioned, 50% of that will be reimbursed.

It is about the construction execution. This can vary greatly and accordingly influence the construction costs.

For the energy consultant, it does not matter whether he calculates or proves based on the reference value. He uses the same for both.

Some people really make a science out of it. I checked again with us, we're talking about 2,300 euros net for the all-inclusive package. As stated, 50% of that will be reimbursed.

The offer I have shows costs of almost EUR 8,000 gross. Included services: energy balance with KfW55 target, 30x individual thermal bridge verification, KfW application, energy certificate, KfW construction supervision, proof of summer thermal insulation

Are too many services being offered?

I was also quoted €2000 over the phone by the expert. If he is also supposed to accompany a regular construction supervision for general quality control, an additional €3000 for 6 or 7 on-site appointments etc. will be added.

The offer I have shows costs of almost EUR 8000 gross. Included services: energy balance with target KfW55, 30x individual thermal bridge verification, KfW application, energy certificate, KfW construction supervision, proof of summer thermal protection

Are too many services being offered?

Maybe get 2-3 more offers?

The offer I have shows costs of almost EUR 8000 gross. Included services: energy balance with KfW55 target, 30 individual thermal bridge calculations, KfW application, energy certificate, KfW construction supervision, verification of summer heat protection

Are too many services being offered?

hm, how does he know that it will be 30 thermal bridge calculations?

Let me elaborate a bit: If the flat-rate thermal bridge surcharge of 0.05 W/(m² K) is not sufficient for KfW55, each individual thermal bridge will need to be calculated, which can cost a three-digit amount per thermal bridge. Therefore, at first glance, the offer is not completely unjustified (though additional offers never hurt).

It is possible to dispense with a thermal bridge calculation and still achieve a KfW55 house using a flat-rate thermal bridge surcharge of 0.05 W/(m² K), but then you either have the luck of benefiting from lots of glass area and a south side to take advantage of solar radiation, or you compensate with thicker insulation on the floor slab, exterior insulation, or roof.

Or you do a "KfW Efficiency House 55 according to reference values." In this case, you also have the option, using the KfW thermal bridge short method, to achieve a value of 0.035 W/(m² K).

But that’s something the structural engineer/energy consultant should check: which method is more economically sensible. Therefore, the structural engineer perhaps shouldn’t just offer 30 thermal bridge calculations flatly at first but should first see if it is even necessary.

Talk to your structural engineer about KfW55 according to reference values and ask him whether that might be more sensible or not.