Is an inhabited basement part of the thermal envelope or not?

whether the basement with the only partially used living space "guest room" should remain in or out of the thermal envelope

If it is officially called a guest room, it will have to be included in the area complying with the Energy Saving Ordinance, I "fear" and see the question as settled due to lack of alternative options.

It's nonsense to spend 50-70k on a basement and then consider removing it from the thermal envelope. How much savings is that supposed to bring? You can't change that later.

If it is officially called a guest room, it will have to be included in the energy saving ordinance-compliant area, I "fear" and consider the question resolved due to lack of alternative options.

Officially, the thing is then called storage room and simply used as a guest room.

If money is no limiting factor, then everything into the thermal envelope, underfloor heating everywhere and controlled residential ventilation. We are currently building it that way too, it's simply a gain in comfort and comfort just costs.

Have you ever recalculated what you would save if the basement were outside the thermal envelope? Unfortunately, I can hardly recalculate at the moment due to lack of offers.

If someone only comes 2-3 times a year, they can either sleep in one of the office or hobby rooms, maybe even in the living room, or you put an electric storage heater downstairs.

But to heat a basement room that is not inside the thermal envelope with an electric heater, the room should also be insulated, otherwise you'll never get it warm, right? You conduct the heat from the electric heater through the WU concrete (whose U-value I don’t know, but it’s probably very high) directly to the outside into the ground.

How does the insulation of a basement that is inside the thermal envelope differ from a basement that is no longer inside it? Both should have perimeter insulation outside (how thick) and below it stands on a proper layer of glass foam gravel, right?

It’s nonsense to spend 50-70k on a basement and then consider taking it out of the thermal envelope. How much savings is that supposed to bring?

Unfortunately, I lack construction experience and especially offers that I could compare. Do you perhaps know?


Which thread?

Have you ever calculated what you would save if the basement were outside the thermal envelope?
Unfortunately, I can't compare well at the moment due to a lack of offers.

We haven't calculated it because having everything inside the thermal envelope was the only option for us from the start. I estimate the additional costs at 4500 for insulation and 6000 for building services. The floor area is 10 x 12 m. Since we wanted living-quality space, quite a few other items were added, such as higher rooms, good plaster/floor coverings, more sockets/LAN, etc...