Need help with the energy saving calculator

Hello dear house-building forum,

I am looking for new windows for my home. I am annoyed that I am only thinking about it now in the freezing winter. At the moment, there are old wooden windows installed. To make it easier for me to choose new windows, I tried an energy-saving calculator.
Now I need information about the indicated unit. Furthermore, I might need a general advice on what types of windows seem sensible (e.g., X chambers). Among the offers are, among others, "Rekord Kunststofffenster." Are wooden windows still sensible at all?
Please do not come now with comments like: "Go to a specialist shop and get advice there."
I really only need a rough orientation, which is why I resorted to the energy calculator. Generally maybe wood vs. plastic and then also which type.
Thanks in advance.
Ruediger

Hello Ruediger,

Go to a specialist store and get advice! What is wrong with that?

Your question is way too general and much has already been written about windows and specifications.

Regarding the choice of material: Who still wants plastic today? Who wants it to be obvious at first glance that they have the cheapest windows in the house? Who still wants non-decomposable material that later has to be disposed of as hazardous waste?

Best regards

K.Brodbeck