ᐅ Additional Insulation in the Ytong Basement (36 cm)?

Hello everyone,

Despite searching extensively, I haven’t been able to resolve the question about insulating our basement. Maybe you can help me?

We are building a detached house with a basement made of 36cm (14 inches) Ytong blocks. The basement includes a self-contained apartment and an office. The concrete slab has already been insulated with 10cm (4 inches) of perimeter insulation.
Both the energy consultant and the architect said that no additional insulation is necessary for the basement walls, as the Ytong blocks provide sufficient thermal insulation there.
The overall construction of the house is single-layered, so without additional insulation.

Does it make sense to insulate only the outside of the basement, or can I save the money?

Best regards!

Rorolly schrieb:
Basement made of 36cm (14 inches) Ytong blocks. The basement contains a granny flat and an office

... is the entire basement below ground level?

Bauqualle schrieb:
... is the entire basement below ground level?

The house is built on a slope, so the front part is partly above ground. However, more than 70% is still below ground level.

Hello,

Rorolly schrieb:

We are building a single-family house with a basement using 36cm (14 inch) Ytong blocks. The basement includes a granny flat and an office. The floor slab has already been insulated with 10cm (4 inch) perimeter insulation.

Whether this is sufficient or not must have been calculated somewhere.......

Best regards

Hello,

according to the calculations, it should be sufficient. It’s just a thought whether it might be better otherwise.

The current setup is:
Cold-applied adhesive membrane system "Bituthene"
Sulfiton DS system protection drainage and backfill protection sheet with additional slip layer and filter fleece

The optional setup (at an extra cost) would be:
Cold-applied adhesive membrane system "Bituthene"
Jackodrain (XPS boards with studded drainage membrane and filter fleece) thickness 60mm (2.4 inches)

I would be interested to hear your opinions on this...

... are you referring to the foundation slab? ... or is your question specifically about the exterior walls that are in contact with the soil? In that case, it is crucial to know which heated rooms in the basement are directly adjacent to exterior walls that will be backfilled with soil ...