How to Paint Old Aluminum Siding

Scrape away rust with a wire brush.

If you paint old aluminum siding, you'll have to address a pair of important issues. First, unlike wood surfaces, aluminum siding is ill-suited for paint adhesion and must be abraded with a special type of primer that will condition the surface to accept paint. In addition, if your aluminum siding is old, you may need to remove and seal rust with a specific type of coating, or the problem will recur.

Things You'll Need

• Pressure washer
• Wire brush
• Acrylic-based red oxide primer
• 3- to 4-inch latex paintbrush
• Galvanized metal etching primer
• Roller
• 2 nap roller covers
• Exterior acrylic latex paint

Instructions

1. Clean the old aluminum siding, using a pressure washer. Allow the siding to dry out completely.

2. Scrape away rust, using a wire brush.

3. Apply an acrylic-based red oxide primer to the rusted areas with a paintbrush, effectively sealing them to prevent recurrence. Allow the primer to dry for two hours.

4. Wash the brush with water.

5. Abrade the aluminum siding to promote adhesion by applying a coat of galvanized metal etching primer, using the roller. Allow the etching primer to dry for two hours.

6. Wash all painting tools with water.

7. Apply a coat of exterior acrylic latex paint to the primed aluminum siding, using the roller stocked with a fresh, clean nap roller cover.

Tips & Warnings

• Do not paint over aluminum siding without using an etching primer to abrade it, or the finish will peel.

• Do not use an oil-based red oxide primer, or you may have adhesion problems when you apply the etching primer.

Resources

• Popular Mechanics: 5 Pro Painting Tips Every Amateur Should Know