Let’s approach this in 2 steps: first the window frame and then the glass surface itself. Step 1: Window frames This one-piece, seamless frame is made of polypropylene which doesn’t fade over time. You can use the same product you use to clean the glass surface. Use a soft cloth or a sponge. Wash with a non-abrasive cleaner. Don’t use gas or paint thinner. Step 2: Glass Surface Regular glass, single or thermo-pane. Use a mild detergent such as dishwashing detergent or the one you use to wash your car. Alternately you can use a homemade water and vinegar mixture for cleaning. Apply with a clean, soft cloth, a paper towel or a non-scouring sponge (nothing with an abrasive surface). Do not use an abrasive cleaner as you risk scratching the glass. Acrylic glass Use the same instructions as for regular glass (above). Window models with Decorative Inserts A Decorative Insert is installed on the interior side of the window. It fits in a slot in the window frame. Gently lift the insert, starting in one corner. There are 4 fasteners that hold it in place. Clean the glass surface as for regular glass. As for the insert itself, it is made of plastic. Clean it the same way as the window frame. Polycarbonate (LEXAN) Use a sponge with lukewarm water and a mild detergent. Do not use abrasive or highly alkaline cleaners. Never use a scraper, razor blade or other sharp instrument on the polycarbonate. Don’t use gas or acetone. Avoid cleaning in full sun or hot weather. Rinse everything well, using a garden hose for large surfaces. Very important: Do not wash your garage door or its windows with pressure washer. Instead, use a garden hose. If you use a spray nozzle on your hose, use the light shower setting, not the strong direct jet.