The windows on our 13 year old house are metal double pane. Each time it gets cold we get condensation inside which caused rotting on some of the window sills. I have replaced the rotted window sills with marble. The problem is that there is nothing that stops the cold air from the outside to the inside. The window is metal against metal. Shouldn't there be something that seperates the metal frame around the glass from the metal fame it sets in? We get ice build up on the inside during the winter in cental Oklahoma where it does not get severly cold. Is there a fix for this problem without replacing the complete window and frame? I have thought of adding some inexpensive storm windows.