How do you clean really dirty windows?
For exceptionally grimy windows, add some vinegar or ammonia to the solution. If you’ve really got buildup, vinegar will cut through grease and grime.” Lewis says to wash the edges of the window glass first, rinse and then give the whole window a go.
How do you clean windows that have not been cleaned in years?
Combine water, white vinegar and dish detergent in a bucket. Increase amounts as needed. Using a soft bristle scrub brush on an extension pole handle thingy, dip the brush in a bucket of the solution, and scrub it on the window. Before it has a chance to dry, spray/rinse it off with clean water.