Painting Metal With Latex Paint (Can You Do it & How to)

Metal is non-porous, so painting it is hard. So, can you use latex paint on metal?

You can use latex paint on metal. but the paint isn’t durable so you must seal it for outdoor surfaces. You also need to apply a primer before painting. 

Latex paint isn’t water-resistant, so it won’t protect metal surfaces from moisture or water. However, if you seal the paint, its finish will protect the surface from water and moisture. 

Priming is Necessary

You shouldn’t apply latex paint on metal without a primer. That’s because metal is a non-porous surface, and latex won’t stick to it without a primer.

For the paint to stick, it must penetrate the surface. But, since metal is non-porous, the paint won’t be able to penetrate it and won’t stick. So, you must apply a primer first.

Compared to paint, a primer is formulated with extra additives to increase its bonding qualities. So, a primer will stick to the metal without penetrating the surface.

The primer will provide a smooth and even layer (base coat) for the paints to stick to. So, latex paint will penetrate the primer coating and stick to the primer.

If you apply it without a primer, the finish will start peeling off after a while.

How To Apply Latex Paint On Metal?

Applying latex paint on metal isn’t hard, but it requires a lot of prep work.

Here are the tools you need:

  • Water
  • A metal scraper or wire brush
  • Sandpaper
  • Latex Paint
  • Paintbrush
  • Primer (optional)

Now let’s get to work.

1. Wash And Clean The Surface

Wash And Clean The Metal Surface

First, wash and clean the metal surface. Cleaning will remove the filth and dust and allow the paint to stick properly. 

To wash it:

  1. Mix soap with warm water. 
  2. Pour the soapy water over the surface and use a soft brush to scrub it.
  3. Once you clean it, use clean water to rinse the surface. 
  4. Remove soapy water residue.
  5. Allow it to dry. 

Don’t use detergent because you can ruin the metal surface. 

2. Prep Your Workspace

Prep Your Workspace

While the metal is drying, you should prep your workspace. Remove (or cover) objects near your workspace to prevent paint spills over them. Also, cover the floor with plastic wrap or a large drop cloth, especially wooden floors.

3. Scrape The Metal

Scrape The Metal

You must scrape the paint off if the metal surface is painted (or sealed). To scrape the existing finish off, use a metal (or plastic) scraper. Just put the scraper under the paint, and lift it. You won’t be able to remove all the paint but remove as much as you can. For the leftover use paint stripping compound. 

If the metal surface isn’t painted, you can skip this step. 

4. Sand The Metal

Sand The Metal

Use coarse sandpaper (60-grit) to sand the metal. Sanding will remove imperfections, bumps, or any leftover paint from the surface. Also, it will provide a smooth surface for the paint to stick to. After you sand with coarse sandpaper, use fine-grit sandpaper to finish the sanding process.

After you are done, the metal surface will be rough. If you don’t want to scratch the metal while sanding, wet-sand it instead of dry sanding it.

5. Apply Primer

Apply Primer

A primer will improve the bonding between the latex paint and the metal surface. A primer will provide a smooth textured layer and will also hide (cover) imperfections on a surface. Use latex primer or self-etching primer for this. 

To apply a primer, use a brush or roller and apply 2-3 coats. You must wait until the primer dries before applying a new coat. 

6. Apply Latex Paint

Apply Latex Paint On Metal

Once the primer dries, apply 3 coats of latex paint. To apply latex paint, use a brush, roller, or sprayer. If you use a sprayer, you must thin it with water. 

After the last coat dries, seal the finish. To seal latex paint, use polyurethane or varnish. These sealers will produce a thick glossy layer over the finish and protect it from moisture, water, and scratches. 

Latex Paint Dry Time on Metal

On metal, latex paint dries enough for a re-coat within 3 hours. This means you can apply another coat after 3 hours.

Latex paint dries fast because of its water-based nature. The solvent (water) must evaporate for the coating to dry. Since water evaporates fast, this means latex paint dries fast too.

If you re-coat too soon, the finish will turn sticky. That’s because the evaporation process will be stopped, and the solvent (water) still be stuck between the new and old coats. Since there’s still water on the old coating, the new coating won’t stick. 

Also, before you can seal latex paint, its coating must cure. It takes latex paint 48 hours to cure (oxidize). Curing (oxidization) is a process where particles harden. Once the particles have hardened, you can apply a sealer. 

Related Read: How To Paint Concrete With Latex Paint?

Metal Doors

You can apply latex paint on metal doors. But, you must strip, clean, sand, and prime the door first.

Metal doors are durable in terms of security but not in terms of design. As a result, metal doors struggle to retain their look and design after the first few years. So to revive the look, you can use latex paint on the door, but you need to prep the door first.

If the door is painted (or sealed), you must remove its finish, apply a primer, and then paint it. That’s because the paint won’t stick to a sealed surface or an oil-based finish. 

You must use a primer compatible with metal surfaces and latex paint. For instance, water-based primers are compatible with both. Also, for outdoor doors, you must seal the finish.

Metal Siding

You can use latex paint for steel or metal siding, but you must use oil-based primer to improve the adhesion of the paint. Also, you must seal the finish with exterior polyurethane. 

However, latex paint isn’t the best choice for metal siding because it doesn’t have the adhesive or protection features to protect it from weather elements. Instead, it’s better to use oil-based paint and an oil-based sealer to protect it from weather elements.

But, for indoor metal sidings, you can use latex paint. Indoor sidings won’t be exposed to weather elements, and latex is durable enough to protect them.

Final Words

You can use latex paint for metal, but you must apply a primer before applying it. Also, you must seal the finish with an exterior sealant for outdoor surfaces. 

Tony Adams
Tony Adams

Tony is a professional painter and an author of DIY Geeks. Tony has completed over 1,000 painting projects for his clients. It's safe to say he knows what he Is talking about,

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