T8 (with perlite filling) instead of KfW70 heating system? How to improve values?

Hello everyone,

I had my house calculated with a T8 36.5 with perlite filling and got the following result:

Annual primary energy demand qp [kWh/(m²a)] 53.79
Transmission heat loss Ht [W/(m²K)] 0.357

Therefore, no KFW70 either, since the transmission heat loss is not below 0.336.

Could that be the case, or with what means could I achieve a better value?

Info: Heating is water heat pump, no solar, no ventilation system

Thanks for your feedback!

Hello,

...I had my house calculated with a T8 36.5 with perlite filling and got the following result:...
So no KFW70 either, since the transmission heat loss is not below 0.336....Is that possible or with what means could I achieve a better value?

Could be - nothing is certain ;-) The calculation would have to be checked for this. So here Ht' seems to be the culprit ;-) Let's analyze according to the percentage shares of the respective losses. Possibly energetic improvements of HT' in other individual components or in total might achieve the desired effect!
Alternatively, a detailed WB proof instead of the flat rate of 0.05 W/m²K according to 4108 Bbl2. However, not cheap (calculation costs) and hard to predict if it will ultimately be sufficient.
However, with a WW heat pump or brine heat pump, assuming exact dimensioning, excessive insulation measures make little economic sense, quite differently from gas condensing boilers, pellets, or e.g. air heat pumps.

Best regards

Thank you for the information and your assessments... I still need to find one or two screws to turn so that with as little effort as possible, the desired effect (the reduction of heat loss) occurs.

The question now is, where is the easiest place to start? At the insulation on the roof or the top floor ceiling?

....The question now is, where is the easiest place to start here? At the insulation of the roof or the top floor ceiling?

Windows, roof, OGD. Just do the math. For example, increase the insulation thickness in the latter case.

Best regards