Underfloor heating or radiators on the upper floor?

Ok thanks, that already helps me. Does anyone here perhaps have experience reports from having spent 2-3 winters in a house with underfloor heating on the upper floor?

..Are afraid that the rooms won't heat up quickly enough because of the underfloor heating upstairs! What would you advise me???

Underfloor heating systems exist in a considerable variety with sometimes very differentiated performance, constructions, and control behavior. You don't have to freeze with underfloor heating, provided it is properly dimensioned. However, it is less suitable for shutdown operation (inertia). In this case, "continuous operation" is usually sensible (required), ideally with a nightly setback operation of about 2K. Important in this context is the heat generator. With heat pumps, for efficiency reasons, as low flow temperatures (VLT) as possible, <= 35°C, must be achieved. However, this makes the heating surfaces larger (more expensive), and in rooms with high heating loads (e.g., bathrooms), additional heating surfaces (wall heating) are sometimes required. With conventional heat generators, VLT of 40...< 50°C are unproblematic.
Best regards.

€uro I think is already right. What kind of heating system do you have? Generally, I would say: underfloor heating everywhere, and you are well prepared for the future. With appropriate installation (spacing), a heat pump can also be used later. In any case, I no longer want to do without underfloor heating throughout the entire house. Regards...