If the spots are really tough to remove your best option is to use undiluted vinegar.
Best way to clean outside windows diy.
Wait for the window to dry.
Scrub the glass with a wrung out sponge.
Green living from national geographic recommends this simple recipe plus a few extra tips for the best window cleaning outcome.
Dip a clean microfiber cloth or mop head into the solution and attach to the mop handle.
Outside windows typically have more dirt and stains.
For divided lite windows use a sponge and a small squeegee.
Use a separate clean rag to wipe the perimeter of the glass.
Scrub your exterior windows with the mop.
Rinse and dry the window frames immediately to avoid any damage.
Microfiber rags work great for window cleaning.
Put vinegar in a spray bottle then spray a large area of the window and clean until clear.
Clean only when there is no direct sun on the windows.
Ideally windows should be washed twice a year but it s a task most people don t look forward to.
Once most of the crud is gone move on to the next step.
If you can t find a small enough squeegee you can cut off a larger one to fit your glass size for a diy window cleaner.
Second using a solution of 50 water and 50 vinegar clean the windows and then rinse them off.
Spray a streak free window cleaner onto the glass or on a clean microfiber cloth and wipe.