Fairly light, yet strong and durable
Despite their light weight, aluminium windows and doors are of very high quality. Their extreme stability and resistance against deformation makes Reynaers systems meet the highest European standards in burglar resistance, or even bullet resistance.
Aluminium is a metal. It does not absorb any moisture and therefore it doesn’t expand. It does expand from heat, but the extremely firm corner connections make sure that you won’t notice these expansions. What’s the most important benefit? There won’t be any cracks or ruptures, not even after many years.