Renew windows, which material?

Hello everyone,



We are planning to replace all the window panes in our entire house. It is a 3-story 2-3 family house. Built around 1970.



The panes are accordingly old and not energy efficient, and in summer especially the rooms on the top floor heat up extremely due to roof windows.



I absolutely have no knowledge about windows. I assume that triple glazing insulates better and is therefore also better than single glazing. I hope I am right with this assumption :-D



Now there are different materials for the frame: wood, aluminum, plastic, hybrids, and who knows what else. Is there a source on the internet where one can find out which material is best for which situation? Unfortunately, I couldn’t find anything :- Or can someone here in the forum explain it to me?



I have heard that plastic probably expands too much under strong sunlight and therefore the windows become hard to open and close. But this could also be just pub talk. I hope someone brings some clarity here :-)



If it’s relevant: almost all windows are to be replaced. There are both “normal” sized as well as floor-to-ceiling, about 3 meter wide windows, and also roof windows involved. One long side of the rectangular house faces completely south and is fully exposed to the sun in summer.



I hope someone can help me and I thank you in advance :-)





Best regards



Fiego

Hello Fiego,
in advance: I am not an expert or a professional, but I have had one experience. I have double-glazed plastic roof windows from Velux and ordered the Velux blackout roller blind at the same time. If I make sure to lower it in the morning during summer and only open it again in the evening when the sun is no longer shining on it, it insulates well. If you leave the blinds up all day, there is a noticeable difference and despite the insulation, it gets significantly warmer.

Professionals will surely chime in.

As a rule, modern roof windows hardly expand at all in extreme heat - this is taken into account during manufacturing. Especially for windows in the attic, good sun protection and heat protection are important, and I can only agree with HuggyLilly on this - however, this can also be added later at low cost. In recent months, we have had excellent experiences with heat protection pleated blinds - thanks to a rear coating, they reflect heat optimally.