Should You Paint Steel Siding?
Your steel siding will either be coated with paint and primer or be galvanized with a zinc coating to protect it from rust. Steel will rust, regardless of the coating, though galvanized steel should resist rust the longest.
Even if the steel siding has a decent coat of paint or is galvanized, it is worth making a regular inspection of the siding for rust. Once rust has taken hold of steel, it can be difficult to repair the damage and stop the rust from spreading further.
If the steel is galvanized, the zinc coating should last up to a half-century before it rusts apart. This is one of the major reasons why galvanized steel facades are so popular is that they are low maintenance and tough.
The paint on regular steel siding may last up to 10 years, but you should look at painting it every 5 years. You may escape having to paint everything and limit it to repair and touch-ups. But you should still repaint all the siding after a decade with a gloss or latex coating.
The cost of repainting steel siding ranges from $1.50 to $3 per square foot if you do it yourself. This is a big saving compared to replacing the siding which costs anything upwards of $6 per square foot.
Is It Easy to Paint Steel Siding?
With the right products, painting steel siding is a simple task, and the results should be as satisfactory as if you were paying a professional. You will need to carry out a basic inspection before performing the repairs, but even this should not be a problem for an amateur.
What Kind of Paint Do You Use on Steel Siding?
Before painting a metal surface, you should consider whether you need to use a primer. The primer will set the surface up for better adhesion to your paint and add an extra level of protection over the metal.
The two main types of paint for steel siding are gloss and latex:
An enamel coating will give the steel a corrosion-resistant glossy coating that is easy to wash down with a hose.
Though you can use water-based metal paints for steel siding, oil-based paints are a more common option for external use. The oil in the paint inhibits rust and is more effective at waterproofing steel.
Modern latex paints tend to be water-based, so begin with a primer when painting bare steel.
The latex formula is less prone to splitting since it can stretch and flex with the metal. These latex paints dry faster and are safer to use than gloss if you are painting steel siding in an enclosed space such as inside a garage.
Out of the three most common finishes of gloss, satin, and matt, gloss is the best choice for outdoor metal siding. Gloss offers the best rain run-off surface, reducing the time water can eat through the paint and begin rusting your steel. Satin is also a good finish for rain runoff.
Matt looks good in the beginning, but dirt and scale will cling to it. Both scale and mud are excellent substances for eating through paint and causing rust. There is also a range of colors to consider, such as natural, pastels, brick red, and shades of grey and white.
White gloss can keep a home looking fresh. On the other hand, greys, garden browns, and greens can help to blend the siding into the surroundings. Darker colors will hide the dirt but also never look clean.
Medium to light grey-blue paints are a good match for steel, as they match the metal. These lighter hues are also a reasonable choice for most neighborhoods.
How to Prepare Steel Siding for Painting
Before getting to the paint stage, you need to clean and prime the metal surface. Old flaking and cracked paint will need to come off, and you need to remove dirt, oils, and any other contaminants that will repel the paint.
Scraping, washing, and sanding the steel will give you a chance to inspect the siding for damage and to make repairs. A clean surface is also better for primer and paints to adhere to, and it will reduce the chances of your new paint flaking off when it dries.
Priming Steel Siding
Reasons for using a metal primer include smoothing the transitions between old paint and bare steel. And the Primer gives your new paint a tacky surface to stick to. Some paints include a primer in their mixes.
How to Paint Steel Siding
- 100-grit sandpaper
- Electric sander or a pressure washer
- 1-inch-thick roller
- Edging brush
- Soap water and sponge
- Mineral spirit or degreaser
- Drop cloth
- Painter’s tape
- Plastic masking
- Clean up rags
- Goggles respirator
- Scrape or Pressure Washer – It is a lot of work to remove all the old paint, so limit the scraping to the rough patches and big flakes. A pressure washer may work, but this means you will have to wait a long time for the siding to dry out before you can paint.
- Sanding – Use 100-grit sandpaper on an electric sander and go over everything that you are going to paint. This grade of sandpaper should remove the smaller flakes and even out the surface. You want to rough up all the remaining old paint to make for a better painting surface.
- Degrease – Old paints can leave oils behind, or they may have been applied over grease, which caused flaking. If the surface is still oily after sanding, use a degreaser to remove the oil from the siding.
- Protect – This is the time to lay down your drop cloth and mask-off areas with painter’s tape and plastic. Metal paints and primers are hard to remove, and once they sink into wood and concrete, they are near impossible to clean off.
- Primer – Mix the primer with the recommended amount of thinning solution. Use water for water-based paint and mineral spirits for oil-based paints. Do not blend the paint with the wrong thinner. Apply the primer with a brush or roller.
- Paint – After 24 hours, the primer should be touch-dry to sticky. A good time to paint is when the primer is still tacky.