Renovate your home green!
You are still looking for a better alternative to KAPO? Save your energy.
Wooden windows are better than the quite common plastic ones. The frame material PVC consists mainly of oil, that consumes already a lot of energy in the production cycle and produces CO2 emissions when disposed. Trees on the other hand absorb CO2 when they grow and store it in the wood. Wood provides the perfect room climate as it does not conduct hot or cold. It also regulates the humidity in the room and thus ensures a comfortable interior climate.
It is obvious: a natural renewable raw material is the best from the ecological point of view - no complex ecological balance is required to see the truth in this statement