How To Paint Galvanized Steel Roofing Panels Banner

Galvanized steel is often used as roofing panels because it is highly durable and resistant to water damage. Some people will leave a galvanized metal roof as is, whereas others prefer to paint it. However, if you have to repair your galvanized metal roof anyway, it might be a great visual decision to paint it afterwards. Read on to learn how to paint your galvanized steel roof and, if necessary, repair it.

Understanding Galvanized Steel

Galvanized steel is produced by coating steel with a protective layer of zinc. This process, known as galvanizing, protects the steel from corrosion. When it comes to painting, though, the very zinc layer that shields against rust can also make it tricky for the paint to stick directly onto the surface. But worry not! Below, we thoroughly explain the process you’ll need to follow.

Step-by-Step Guide to Painting Galvanized Steel Roofing Panels

Materials That You Will Need:

  • Rust Inhibiting Exterior Metal Primer
  • Acrylic Exterior Paint
  • Paint Tray
  • Paintbrush
  • Paint Roller/Handle
  • Ladder/Broom
  • Rag/Bucket
  • Scrub Brush
  • Pressure Washer (optional)
  • Sandpaper
  • Handheld Electric Sander
  • Trisodium Phosphate or another Cleaning Agent

1.  Prep

  • Pick a nice partially cloudy day with no chance of rain to start off this project. You’ll need to be outside most of the day, so weather with cloud breaks will help prevent accidental sunstroke. Be sure that you do not pick a day when you notice environmental debris circulating in the air (leaves, weeds, etc.), or else it will ruin your galvanized roof paint job.

2. Repair

  • If you find any spots that have rusted, you’ll need to sand them down with a handheld electric sander. It shouldn’t be too hard to repair this because galvanized steel roofing is treated with zinc oxide to prevent destructive rusting.
  • Set up your ladder and start by brushing the roof clean of any dirt or debris with a scrub brush or broom. If you feel it’s necessary, use a pressure washer to clean the surface area as well. You can also use a bucket of cleaning agents for galvanized steel roofing and a rag to ensure the roof is very clean. Then let dry.

3.  Prime

  • Get your rust-inhibiting primer ready in a paint tray and, using a paint roller, apply the primer to each steel roof panel. Make sure you cover the roof entirely. The primer will protect the steel roofing and allow optimal results when you apply the paint.
  • Using a paintbrush, paint in any spaces that were left untouched by the roller (screws and cracks will need to be primed over). Allow the primer to dry as instructed on the primer can.

4.  Paint

  • Using your exterior metal acrylic-based paint, using the same paint tray that has been emptied of any remaining primer, begin to apply the paint with a roller directly onto the galvanized steel roof panels in the same order you applied the primer.
  • Be sure to cover the entire surface so that you cannot see any primer left. Allow to dry. Usually, leaving it overnight will ensure it has dried completely.

prepping to paint galvanized steel roof
painter painting galvanized steel roofing panels

Common Mistakes to Avoid When Painting Galvanized Steel

When painting galvanized steel roofing panels, it’s crucial to avoid certain mistakes that could lead to poor adhesion, premature peeling, and reduced longevity. By steering clear of these errors, you can ensure a successful, long-lasting paint job.

Mistake 1: Insufficient Surface Cleaning

Properly cleaning the surface is key to achieving a smooth, long-lasting paint job. Dirt, grease, and debris can prevent the paint from adhering to the steel, causing it to peel prematurely. Ensure that the surface is thoroughly cleaned and degreased before beginning the painting process.

Mistake 2: Skipping the Galvanized Metal Etching Primer

Applying paint directly to galvanized steel without using a galvanized metal etching primer is another common mistake. The primer ensures proper adhesion between the paint and the steel surface. Without it, the paint may not stick correctly, resulting in peeling or flaking paint.

Mistake 3: Using the Wrong Paint

Not all paints are suitable for galvanized steel. Choosing the wrong paint may lead to issues such as poor adhesion, peeling, or premature fading. It’s essential to use a 100% acrylic latex exterior paint specifically designed for galvanized steel applications. This is the best paint for a galvanized metal roof.

Mistake 4: Applying Too-Thick Coats

Two thin coats of galvanized paint usually provide better coverage and durability than a single thick coat. Do not heavily load the brush or roller and instead apply the paint in thin, even layers. Thick coats can lead to uneven drying, causing the paint to crack or peel over time.

Mistake 5: Ignoring Weather Conditions

Painting in extreme weather conditions can affect the drying and adhesion processes. High humidity, excessive heat, and low temperatures may cause the paint to dry too slowly or unevenly. Check the paint manufacturer’s guidelines for ideal weather conditions and plan your painting job accordingly.

Mistake 6: Neglecting Maintenance

Proper maintenance is essential to keep your painted galvanized steel roofing panels looking their best and protected. Neglecting regular cleaning, inspections, and touch-ups can result in faster deterioration of the paint. Commit to a proactive maintenance schedule to maximize the lifespan of your paint job.

By avoiding these common mistakes, you can successfully paint your galvanized steel roofing panels, ensuring they look great and maintain their protective qualities for years to come.

Safety Measures

  • Using a drop cloth or tarp, it’s a good idea to cover the area around the roof that you don’t want paint to fall on.
  • If your roof has a steep slant, it is best to have another person assist as a safety precaution.
  • Use a safety harness when working, especially when painting old galvanized metal roofs to prevent falls.
  • If etching primer or paint comes into contact with your skin, wash it off immediately.
  • Always wear the recommended protective gear, like goggles and gloves.


Painting galvanized steel roofing panels is an effective way to provide an extra layer of protection and enhance your home’s curb appeal. Follow this step-by-step guide to ensure a proper paint job.


Now that you have learned how to paint your galvanized steel roofing panels and repair any minor rust damage, you’ll have a unique-looking steel roof that will turn every head on the block! But if you can’t find the time to complete this project on your own, or your galvanized steel roof is too dangerous to attempt to paint, why don’t you call Home Painters Toronto and we’ll do it for you? Call us NOW at 416-494-9095 or email us at And don’t forget to follow us on all our social channels below!