Not surprisingly, wood clad and fiberglass window frames rated the highest. (These replacement windows also carry the greatest price.) These window frame materials are better at staying out the rain, wind and aspects. Each window was put through a week of extreme temperatures to see how the window broadened, contracted and bent with temperature level and condition modifications. Each window was then evaluated for water and air leakage. Windows that showed little or no change in efficiency from the start to finish were ranked greatest.

Naperville Windows and Doors