Cost to renovate a complete house

Received the energy certificate today. I thought it would contain more recommendations. Only basement ceiling insulation, new windows, and solar thermal energy are mentioned. Primary energy demand is 228.5 kWh/(m2*a), final energy demand is 206.

U-value building envelope (that is the Ht-value, right?) is 0.89. According to the internet, that is pretty bad, isn’t it?

Yep, that’s the HT – I don’t think it’s all that bad for an old building (without any measures, it would be well over 1 or 2). Unfortunately, it’s not very meaningful because it represents an average value over all building components. They might have once insulated the roof with KMF and installed new windows in the 90s.

But it’s irrelevant for you anyway, since everything is supposed to be new.

Yes, that's true, the roof was insulated at some point, I am still waiting for the answer when and with what. Some of the windows are also at least newer than the 60s. The values at least confirm my suspicion that the facade also needs to be insulated (only 24cm at the moment).

The facade has 24cm insulation??

I still don't believe that you can turn an old building into a new building at lower costs. The costs are the same or even higher. Normally, people buy an old building because they like the charm or prefer to carry out renovations/restorations gradually.

If you want to live in a new building, this will only work to a limited extent with the renovated old building. You always have to accept a few inconveniences.

Sorry, expressed incorrectly. The exterior walls are 24cm thick, there is no insulation.