Surprised by low gas consumption

Our first billing 2017/2018 Kfw 70, 150 sqm, 8100 kWh gas. But it didn't surprise me, I planned with 9000. Google also spits that out for energy efficiency..

160sqm, kwf 55, this year we will have about €450 heating costs + €150 for hot water, LWWP. I had hoped for a little less, I think next year the flow temperature will settle a bit lower.

May I ask which 24 cm aerated concrete you used? It's surprising that with that you managed to meet the energy saving ordinance. Or are there other measures?

I can't tell you... I think Ytong? No further measures. Town & Country standard...

I have partly read about new buildings with 20,000 or even 30,000 kWh. But those were probably the ones where something went wrong...

160sqm, kwf 55, this year we have about €450 heating costs + €150 for hot water, air-to-water heat pump. I had hoped for a little less, I think next year the flow temperature will stabilize somewhat lower.

Do you know your calculated energy values from back then by heart?

I don’t find it that little at all. We heat 100m2 and the laundry room in the basement. Recently, we burned almost 11,000 KW. However, our house is an old building from 1921, insulation from 1992, the basement is currently not insulated yet, and on the ground floor there are still 3 double-glazed windows from 1992 and a not particularly tight front door from the same year. The basement door to the laundry room is also old. With a new building with better insulation, completely new windows and doors, etc., I would definitely expect significantly less, or am I mistaken?