Garage 8m x 7.5m gable roof, strip foundation, exterior plaster costs

On the shared wall section, the garage roof would then have to touch the residential building body, or do you see it differently?

That is correct. But doesn’t every firmly anchored carport or terrace roof do the same? You just have to find a solution to create a support surface for the roof without damaging the masonry. Probably best at the height of the intermediate ceiling at the ring beam. No idea how such a thing works sensibly. Alternatively, put a second wall next to it. But I don’t understand why the energy saving ordinance should then be at risk. With aerated concrete or Poroton, that is probably all easier than with sand-lime brick with insulation.

Garage external dimensions 6.50 x 9 m
24 hollow block plan stones (attached to the house with insulation mat in between)
Gable roof with waterproof sub-roof & clay tiles
Floor slab with screed and Korodur hard material scatter
Interior plaster
Colored exterior plaster with base
5.50 x 2.25 Hörmann BiSecur garage door
Side entrance door + 2 windows RC2
Electrical including distribution board

In euros approximately 30K

But I don't understand why the Energy Saving Ordinance is supposed to be at risk.

Because of the transfer of cold between components that touch each other, I meant.

24 cm hollow block plan bricks (attached to the house with an insulation mat in between)

... would therefore also be my method of construction.

Thank you for your answers. According to our calculation, we are at about €42,000 without any personal contribution, but that will still be included. They will be 24 cm hollow blocks. After the construction, I will take the trouble to calculate what the garage has cost.