Tips for Painting Aluminum Siding
How to Paint Aluminum Siding
Over time, the color of aluminum siding on a house fades from the sun and needs to be painted. Painting aluminum siding helps protect and beautify the surface.
Preparing aluminum siding for paint is less of a project than preparing painted wood because the coating on aluminum siding usually doesn't peel like painted wood does. However, aluminum develops a chalky film with age and the film should be removed before painting.
The best way to paint aluminum is with an airless sprayer because the sprayed look closely resembles a factory-like finish that looks best on siding. Spraying is also the fastest way to complete this type of paint job.
Buy the Right Aluminum Siding Paint
Buying the paint is almost more important than the prep work because not all exterior paints can be painted on aluminum siding. The best exterior paint to use on aluminum is 100% acrylic and should preferably contain urethane. When in doubt, read the label on the can that says whether the paint can be applied to aluminum siding or not.
The following exterior paints are by far the best for painting aluminum siding:
- Pittsburgh Manor Hall (Pittsburgh Paints)
- SuperPaint (Sherwin Williams)
- Duration (Sherwin Williams)
All three paints are acrylic and work great for aluminum siding. Manor Hall paint contains urethane for a stronger bond. SuperPaint and Duration are self-priming so unless there's bare aluminum exposed, a separate primer isn't necessary in most cases. SuperPaint is probably the cheapest out of the three, but Duration is by far the best, and of course, the most expensive, but it comes with a lifetime warranty.
Clean the Siding
It is important to take the time to clean the siding thoroughly before painting. Older aluminum siding is usually chalky on the surface and this powdery film can prevent the paint from bonding well to the surface.
The best way to clean the siding is with the powerful cleaning agent TSP. It usually comes in a small box and must be mixed with water. Wear gloves when mixing and handling TSP solution because it can cause skin irritation. If you don't want to use TSP, there are special detergents and cleaners for cleaning aluminum siding. TSP does work great though.
A power washer makes the cleaning go faster, but the extreme water pressure can force water behind the siding if you aren't careful. Scrub the siding with the cleaner and rinse it off with a garden hose instead. After the siding dries, wipe your finger on it and there shouldn't be any residue on your finger.
Is Priming the Siding Necessary?
Priming is necessary if bare aluminum is exposed, or if the surface is terribly weathered and peeling. The three premium paints I mentioned earlier don't require an application of primer over sound surfaces. If you're willing to go the extra mile, primer is definitely good, but it isn't always necessary for an aluminum paint job.
If you do buy primer for the siding, acrylic is best. Once again, read the label on the can to make sure it can be applied on aluminum. My recommendation is SealGrip Universal acrylic primer from Pittsburgh Paints. It is an excellent primer for aluminum siding.
Mask the Windows
Spray painting aluminum with a sprayer is best, but there's a lot of masking involved before you can pull the trigger. Cover all of the windows with tape and plastic. I like to use 48" 3M EasyMask film from Sherwin Williams and white tape to cover the windows. The EasyMask film attached to a hand masker works the best. You can buy both at Sherwin Williams.
You will need to mask off the downspouts and anything near the siding that will be exposed to over-spray. Throw drop cloths over the grass and bushes. It does take a while to mask everything, but the spraying will go much faster, as long as everything is covered correctly.
Spray the Aluminum Siding
If you don't already own an airless sprayer then it would best to rent one for couple days, unless you plan to use it throughout the year, in which case buying one is probably better. For more information about choosing a rental, read this article: How to Choose A Paint Sprayer Rental
An airless paint sprayer is electric and plugs into a standard wall outlet. Using a sprayer to paint siding is a huge time saver. You will spend too much time working if you paint everything with a brush and a roller. I always spray two coats of paint on siding. Some premium exterior paints, like the ones mentioned earlier, are one coat only paints.
The best way to spray siding is to start at the top and work from left to right. Don't spray one half of the wall first and the second half last. That could result in a big overlapped line down the middle of the wall. If you spray primer, only one coat is necessary. Find the recommended spray tip size by looking up the website for the paint you're going to use.
Be sure to check out these additional articles about painting: