Work on basement ceiling insulation with stone wool

Hello. I wanted to report back after successful work. Removed wooden panels. Insulated between the roof battens and reattached the wooden panels. The insulation was reduced from 6cm to up to 3cm with a saw due to the low ceiling height. I know 6cm would have been better, but I simply did not want to become lower. I glued with Knauf Perlfix. It works and holds great. The difference with the thermal imaging camera could already be measured at 1.5 degrees between just concrete compared to concrete with 3cm of stone wool. Then, with the 18mm thick wooden panels, it improved by another 0.5 degrees. Conclusion: insulating the ceiling with stone wool is no fun, but you are very flexible because of unevenness. Regarding the power consumption of the underfloor heating on the ground floor, there was not really much less, not significantly less. Whatever. Better than nothing, and I will do the other rooms as well. Thanks again for your good advice!