If your picture windows are on the ground floor and easy to reach, remove all large dirt particles and debris with a shop vacuum or a soft cloth. For a cleaning solution, use a commercial glass cleaner, a vinegar and water solution, or one teaspoon of dishwashing detergent in two gallons of water.
Apply the solution with a soft sponge or strip applicator, and scrub the windows clean of all dirt. Use a squeegee to remove most of the cleaning solution and a lint-free rag to dry the remaining spots. Choose a dry, cloudy day to prevent streaks.
If your windows are not on the ground floor (or if they’re otherwise too high for you to reach the inside or the outside), it is best to call a professional. Talk to our team at Zen Windows Milwaukee for more window maintenance tips.