Insulating the basement ceiling, slight bulge -> what?

I plan to insulate my basement ceiling. However, it is slightly curved. Has anyone had any experience? Possibly with which building materials? Thanks in advance :)

Hello Nissan! Laugh! Please write more about the situation, otherwise so much is just speculation! In general, all common insulation methods are conceivable here.

Sorry, I have already read that the Rockwell Planarock is best suited for this. Regarding the situation: We have a slightly masonry vaulted basement ceiling. But the kitchen, hallway, and living room are naturally quite cold on the feet and I have 2 small children. ;) The basement is about 70m² in size (the heating is also located there). Regards

Have a vaulted cellar and Planarock was also suggested to us.

Have a vaulted cellar and Planarock was also suggested to us.

Due to the curvature, it is almost inevitable.