Mildew grows on canvas awnings that are regularly left damp and in the dark. It may be green or black, and it gives the canvas awning a dirty and unprofessional look. When you are looking to clean your canvas awning and make it look like new, take care of any mildew that has appeared on it.
Mix a solution that is 1-part water to 1-part isopropyl alcohol into a bucket. Isopropyl alcohol is also called rubbing alcohol.
Place the ladder underneath the canvas awning.
Soak a clean, cotton towel in the isopropyl alcohol solution and wring out the excess into the bucket.
Climb the ladder with the soaked cotton towel and use it to wipe away the mildew.
Climb down the ladder, then thoroughly rinse away the isopropyl alcohol and mildew remnants by spraying water onto the canvas with a hose.
Repeat wiping the canvas with the towel and rinsing off with the hose until the mildew has been removed.
Keep dirt and debris from sitting on your canvas awning, as they will encourage mildew.
Do not use bleach to clean your canvas awning. Bleach discolours canvas, leaving behind yellow staining.