Aluminum siding looks great when it's new ... but it can dent, scratch, fade, and corrode easily over time. Painting is a cost-effective way to update your aluminum siding. The end result is beautiful, newly finished siding, which adds curb appeal to your home and could increase your home’s value. Even a beginner DIY-er can paint aluminum siding with patience and just a few simple tools. Read on to learn how to paint aluminum siding.

How to Paint Aluminum Siding

If you're planning to paint aluminum siding, it is best to find a two- to three-day period when the weather will be cool and overcast. Aluminum siding dries best slowly, out of harsh sunlight. Therefore, weather conditions with minimal sun are ideal.

Step 1. Cleaning the Siding: Scraping and Washing

When painting aluminum siding, the most important piece of prep work is careful cleaning. Prepare a bucket of soapy water and towels, sponges, a hose and scraper. If the siding has previous layers of paint, you will need to scrape them off first. Then wash the siding with the soapy water and a sponge, removing as much dirt as you can. Change the sponges as they become soiled.

Use a hose to spray down the siding after you have scrubbed it. Do not use a power washer, as you could end up causing more damage than good. The powerful flow of water might get behind the aluminum siding, leak into your home, and rot the drywall.

Step 2. Let it Dry

Allow the siding to dry for a day or two. Even if the siding appears to be dry after a few hours, it is better to wait the full two days before painting the aluminum siding.

Step 3. Prime

The best primer for painting aluminum siding is a thinned-down oil-based metal-priming paint. A metal or alkyd-based primer mixed with 1 part paint thinner to 4 parts primer will work best on all types of aluminum siding. Avoid using latex primer or paint on siding, because it may cause bubbles to form beneath the paint film. Stick to an oil-based primer.

Step 4. Painting Aluminum Siding

Semi-gloss is the paint of choice for aluminum siding. Satin or eggshell finishes look the best on aluminum siding and they're known for their longevity. Make sure to apply the first coat of paint within 48 hours after the primer. Painting aluminum siding is straightforward and does not require any special techniques. Use a standard paintbrush for application. In most cases, two coats of paint will be necessary. 

Painting aluminum siding is a simple DIY project when done correctly. if you'd prefer to have a pro do the work for you, find a reliable professional painter in your area.

Updated April 22, 2018.