Exterior windows are exposed to all environmental dirt and they get dirty quickly. They are hard to clean during winter! This tip is perfect for your autumn household!
After washing your windows, apply a "Rain-X" type windshield treatment coat.
Photo credit : http: //handyinks.blogspot.ca/2 ...
It makes sense when you think about it ... This product acts like a kind of wax and it prevents the dirt on the windows. If it works for the car windshield, it works on any windows!