How to Paint the Inside of Gutters

Clear out leaves, limbs, dirt and debris from the insides of the gutters. Be sure to wear heavy-duty garden gloves when clearing away debris. You can minimize ground cleanup by tying a trash bag or lawn and leaf bag to the ladder and filling it with the contents of your gutters as you clear them out.

Scrape away any loose paint from the insides of your gutters with a paint scraper. Use a garden hose to rinse paint chips out of your gutters.

Scrub the inside of the gutters with dishwashing detergent and hot water. A grout sponge works well for this task, although you can use a wire scrub brush as well. Avoid the temptation to rely on a pressure washer to clean your gutters--pressure washers tend to leave behind a thin layer of dirt that can prevent paint from adhering to the metal surface. Rinse out the gutters and allow them to dry completely.

Choose a clear acrylic bonding primer or an oil-based metal primer. Avoid any primer that contains ammonia--the reaction of ammonia with oxidized aluminum can cause paint blisters. If you choose an oil-based primer, add 16 oz. of thinner per gallon of primer for easier application. Paint the inner surface of the gutters evenly with primer and allow it to dry.

Apply pure acrylic paint over the primer to create a protective coat. Ideally, the final coat should be applied within 48 hours of primer application. This will create a stronger bond between the primer and the acrylic paint.