KfW 40 plus - Circulation pump allowed?

Hello,

we are building our house according to KfW 40 plus, the general contractor says a circulation pump for hot water is not possible because otherwise no KfW 40 plus, but when I look at KfW itself, for example in the template for "Bestätigung zum Antrag (BZA)" it literally says under point 2: "A drinking hot water circulation is permitted."

Does anyone have KfW 40 plus with a circulation pump?

And another question, by what latest date should the heat demand calculation be done by the general contractor? And by when should the applications for KfW 40 plus be submitted by the general contractor? We have now submitted the building application, would now finally like to finance but there is still no data regarding KfW from the general contractor.....

Thank you very much, Jörg

Hm does no one have an answer for me?!?

Good question, that's how I read it too.

Six years ago, the statement was also: circulation line with KFW does not work. The energy loss would be too high. The KFW calculation came to us only after the building application and financing signature (we then submitted the KFW calculation).

Relatives of mine have built KfW70 and probably for reasons of energy efficiency should also not install a circulation pump. We have built KfW50 with a circulation pump. Side question: Where exactly does the energy go lost? The insulated water pipes are located inside the insulated envelope after all!?

Hi,

Side question: Where does the energy actually go? The insulated water pipes are located inside the insulated shell, right?

Yup, in winter nothing is lost there anyway because you are heating anyway. In summer, however, with the circulation pump you do have some losses that you otherwise wouldn't have.

This regulation is once again more of an ideological thing.

Best regards,

Andreas