Did you know that based on appearance, next to an untidy bathroom or dirty kitchen dirty windows are how a guest at our home will judge our cleanliness. Windows are expensive and need proper maintenance or they will need to be replaced. Most windows even if not top of the line will out live us all if they are properly cleaned and maintained regularly. I recommend twice a year to keep the glass from being dammaged, and just as important, the seals healthy and leak free. It also keeps the tracks and framing from deteriorating and staining.