ᐅ Energy efficiency question for a 10-year-old house

At the moment, we have a large house in mind. Somehow, we are not making progress with our new construction project.
What confuses us are the following details.
Energy rating A – that would be great, right?
Final energy consumption 145 kWh/m². Wouldn’t that be too high?
Maybe you can help us out.
Thank you, Xinette

As far as I know, the classification of final energy demand according to energy efficiency classes has only existed since the Energy Saving Ordinance 2014 – see graphic...

Then the house would even be rated E according to the new energy saving regulation and would no longer have new building status, correct??? Or am I misunderstanding this???
Thanks and best regards Xinette

Well, I’m not an expert on energy saving regulations, but I believe the 2009 energy saving regulations still apply to existing buildings. You can see where "your" house is located on the chart...