ᐅ Is an energy consultant required for KfW55?

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

It concerns the construction work. This can vary significantly and accordingly impact the construction costs.

For the energy assessor, it does not matter whether they calculate or verify based on reference values. They use the same approach for both.

MarcWen schrieb:
Some people really make a science out of this. I checked again on our side; we are talking about 2,300 euros net for the all-inclusive package. As mentioned, 50% of that will be reimbursed.

The offer I have shows costs of almost 8,000 euros gross.
Included services: energy balance targeting KfW55 standard, 30 individual thermal bridge assessments, KfW application, energy performance certificate, KfW construction monitoring, proof of summer heat protection.

Are too many services being offered?

I was also quoted €2000 over the phone by the expert. If he is to provide regular construction supervision for general quality control as well, an additional €3000 will be charged for 6 or 7 on-site visits, etc.

bluminger schrieb:
The offer I have received shows costs of almost EUR 8,000 gross.
Included services: energy balance aiming for KfW55 standard, 30 individual thermal bridge assessments, KfW application, energy performance certificate, KfW construction supervision, verification of summer heat protection.

Are too many services being offered?

Maybe get 2-3 more quotes for comparison?

bluminger schrieb:
The offer I have shows costs of nearly EUR 8,000 gross.
Included services: energy balance targeting KfW55 standard, 30 individual thermal bridge calculations, KfW application, energy certificate, KfW construction monitoring, verification of summer heat protection.

Are too many services being offered?

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

Let me explain a bit further:
If the standard thermal bridge allowance of 0.05 W/(m² K) is not sufficient for KfW55, then every single thermal bridge must be calculated individually, which can cost a three-digit amount per thermal bridge. From this perspective, the offer is not completely unrealistic at first glance (although getting additional quotes never hurts).

You can skip calculating the thermal bridges and still achieve a KfW55 house by using the flat thermal bridge allowance of 0.05 W/(m² K), but then either you are lucky to benefit from abundant glazing and a south-facing orientation to gain solar heat or you have to compensate through thicker insulation at the ground slab, external insulation, or roof.

Alternatively, you can choose the "KfW Efficiency House 55 based on reference values". Here, you have the opportunity to use the KfW simplified thermal bridge method to reach a value of 0.035 W/(m² K).

This is something the structural engineer or energy consultant should evaluate: which approach is more cost-effective. Therefore, the engineer should not simply offer 30 thermal bridge calculations upfront but first determine if it is necessary at all.

Talk to your engineer about KfW55 based on reference values and ask whether that might be the more sensible option.