Cost of perimeter insulation / floor slab insulation

Hello everyone

Our architect's offer included a non-insulated basement. As a precaution, we have now decided to insulate the basement. CHF 56 per m2 (10 cm XPS) was estimated for the insulation of the floor slab. The perimeter insulation amounts to CHF 28 per m2 (10 cm XPS). I have two questions in this context:

1. When googling, I came across current costs for floor slab insulation (including craftsmen) of EUR 25 per m2. At an exchange rate of 1.5! this would be around CHF 38. Therefore, CHF 56 seems too high for Switzerland as well. Are CHF 56 market-standard?

2. On another page, it states that when insulating the floor slab, one can forgo insulation of the basement ceiling. Is that so? Then our architect would have to include cost reductions that have not appeared so far.

Thank you very much for your feedback.

Hello,
I'll start from the end: If all the exterior surfaces of the basement are insulated, insulation of the ceiling between the basement and the ground floor is not necessary.

Regarding the price of floor slab insulation, one must distinguish whether the insulation is applied before concreting (i.e., between the floor slab and the ground), or over the floor slab and under the basement floor.
The specification "10cm xps" suggests insulation under the floor slab, which would be more expensive than insulating on top of the floor slab.

Craftsmen and material costs cannot simply be compared using a currency converter; I am not familiar with Switzerland in this regard, but I believe that labor costs there are also higher than in Germany. Especially since, due to the EU, quite inexpensive Eastern European companies can also operate in Germany.

Perhaps you can find a German company for this service. It is best to discuss this again with your architect; that is also good for mutual trust.