How to Paint a Rusty Metal Roof – The Easiest Method to Perform It

Have you ever thought of painting a rusted metal roof?

Do you see any rust on the metal roof you have?

Well! Metal, as a ferrous item, is prone to oxidation leading to rust. In the case of the roof, it is more likely to corrode, stains very soon. The surface faces extreme heat, rain, molds, snow, etc. Also, it remains exposed to air throughout the year.

How to Paint a Rusty Metal Roof

One more case is also there. If you live in a shadowy place, under big trees, rust on the metal roof can be feasible there. You may need to clean the top again and again. Unfortunately, the chances of corrosion still remains even if you clean it timely.

Then how will you get rid of rust? From many expert opinions, painting is the perfect way to treat the rusted metal rooftop. In this article, I will encourage you how to paint a rusty metal roof at ease.

Paint a Rusty Metal Roof for Longtime Protection

Going straight to the point – painting the roof requires sufficient time and extreme attention. By attention, I mean your safety and keenness to details while painting the ceiling. Consider this as a do-it-yourself project whether you are a beginner or pro. However, working with a friend or extra person besides you can help better. Okay, let me start with the tools you need:

Tools & Materials

TSP (Trisodium Phosphate)Scraper for paint
Power washerWoolen brush
Heavy-grit (220) sandpaperExtension ladder
Preferable paintPaintbrushes
PrimerRound brushes
SprayerMask/respirator & gloves

How to Paint a Rusty Metal Roof

Here are some steps to follow

When you have collected all the above tools, you can start painting the corrugated metal roof. Follow the below steps carefully:

First Step – Your safety

As you need to stay on the ladder (or staircase) or the roof, there is a matter of your safety. Select a sunny, dry and friendly day. Choosing a day with bad weather can invite accidents. In my case, I would select springtime mostly.

If you want to paint on other seasons, watch out for the day with a clean sky, no chance of rain or cold. Also, working with a friend can help you a lot. When you are on a ladder, your friend can lend a hand, like picking up the paint or holding the ladder. Before you start using brushes, or further actions, put on hand gloves, wear masks for full protection.

Second Step – Rust Removal (Sanding)

Once you are on the rusted roof, figure out how much rust the metal rooftop has. You can follow two methods to remove the rust: pressure washer and Trisodium Phosphate (TSP). Additionally, this step will remove old paints too.

TSP method: TSP can infiltrate the rusts. It enables easy removal of stains and lessens the growth of further corrosion. Anyway, you can find this common chemical at any local store.

Since you covered your face and body well, you can use the Trisodium Phosphate well. Otherwise, it can damage your skin with its harshness. Dilute the powdered TSP in water to make a solution. Keep the ratio of TSP and water like this: one cup TSP and one-gallon water.

After making the solution, apply it with a sprayer and wait for 15-20 minutes. Then, use a paint scraper /a stripper/a woolen brush to remove the rust slowly. Lastly, use a round brush to clean the leftovers.

Pressure washer method: If you cannot find TSP, you can follow this method. Take a portable pressure washer and start spraying the water. Usually, a minimum 2500 PSI pressure washer can be a good choice for rust removal from the metal roof.

Be careful while spraying on the roof; you may slip. Remove all the stains, flakes of rust carefully. If there are still any residues left, you can use high-grit sandpaper (220+). Scrab the whole area and remove the corrodes with a paint scraper. Leave the surface to dry well.

Third Step – Apply Primer

When you are satisfied with rust removal, move to the third step. Remember, removing rust is like sanding the surface. So, there is no extra need to sand the roof. It is time to prime the rooftop.

Applying the primer is always important before giving the main coat of paint. Primer helps the paint to stick on the roof well from the granular point. However, you can find top-quality primers at the market. Some paints have 3-in-1 formula like primer, paint, and finish.

Read the instructions for using the primer well that comes with the product. Take the sprayer and fill it with primer to spray it. There is another solution to use the primer. In such a case, you can use a paintbrush to apply the primer for better results. But it will take more time than spraying a large area.

Priming the area should give you the scope of movement. So, start using a primer from the opposite side of the ladder you put on the roof. It will help you to ride on it freely. After fully priming, leave the surface for 24-48 hours for drying.

Fourth Step – Apply Paint

Once you have done with primer, you can start coloring the roof. I assume you have the right quality metal roof paint with color preferences. Try to use paints with proper rust protection with protective finish feature.

Again, I suggest you check out the weather and ambiance. Stormy or rainy weather can nip the project in the bud. Water on the just-painted roof can peel the primer and paint faster. Now, touch the surface to see if the primer is thoroughly dried.

Follow the same method as a primer to give the base coat. You can spray the paint or use the paintbrush to cover the area. In this case, a roller brush is the best idea as an alternative to the sprayer. Try to put gentle pressure on the brush to get an even finish.

Wait for the time mentioned on the paint container for drying. Usually, it is 6-24 hours. The more you take time, the more the finish becomes solid and sturdy. After fully drying, you can conduct the final step.

Fifth Step – Final or Topcoat

Usually, the topcoat or additional coat is not necessary for small painting jobs. But when you cover a large area, you must give a final coat, especially when you do not prime the surface. You can provide one or more coats to the base coat.

When the entire roof is dried, give the surface another coat of paint. Follow the fourth step to apply the paint. In this step, you can create unique patterns too for an aesthetic look. Again, give the paint time to cure fully. Lastly, you have painted a rusted metal roof well.

Final Words

A painted roof means a healthy and colorful shed over our heads. Painting or repainting a metal roof increases the lifespan of the roof. Also, it helps you saving money in the future.

If you go through the steps I’ve outlined, you will not need to search “how to paint a rusty metal roof” anymore. Now, I hope you will be successful in attending the DIY painting project.

Be careful while putting steps on the ladder and roof. That is all.

Leave a Comment