Believe it or not, it’s possible to give your rusty metal roof a new coat of paint! Read on to find out which painting method works best for you.
It’s recommended to remove the rust on a metal roof before painting over it. Use a homemade vinegar solution or an oxalic acid mixture to remove rust. Prep the surface with galvanized metal primer before applying acrylic latex paint to prevent corrosion.
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How to Remove Rust from a Metal Roof
There are several ways to remove rust from a metal roof! You can make your own cleaning solution from the products in your kitchen or pressure wash the metal surface if you have easy access to your roof.
Contact a roofing company if you can’t access your roof safely. You can also consider renting a cherry picker to clean larger surfaces from tall heights.
Salt, Vinegar, and Baking Soda
Avoid using harsh chemicals on your roof by creating a DIY cleaning solution in your kitchen! First, mix distilled white vinegar with coarse salt – use one cup of salt per gallon of vinegar.
Try to distribute the solution evenly across the roof. You can use a large bucket to spread the vinegar and salt mixture over large surface areas.
Soak the entire metal surface with this solution and leave it for at least 12 hours. You can let the roof soak for up to three days. This homemade mixture will eat away at the rust, so the result will be better the longer you leave it.
After letting it soak, scrub the roof with a foam polishing pad or brass bristle brush to remove the loose rust. Then neutralize whatever is left on the roof with baking soda. Mix one cup of baking soda per one gallon of water to make this solution.
Let the baking soda mixture soak for about ten minutes before scrubbing again with super fine steel wool. Wipe the roof down with denatured alcohol and apply a protectant to prevent rusting.
Keep in mind that the vinegar and salt solution works best for steel roofs. If you have an aluminum roof, consider one of the other options below!
Dish Soap and Warm Water
If the rust on your metal roof is not too extreme, here’s a tried and true solution that works for most cleaning jobs!
Wash the metal surface with dish soap and warm water to remove minimal rust and staining. Scrub the roof with super fine steel wool or a wire bristle brush depending on the roof material.
Oxalic Acid Solution
Another simple method to remove rust is an oxalic acid solution! Mix one part oxalic acid with six parts warm water.
After soaking, scrub the surface with a metal bristle brush and allow the roof to dry. If a handheld brush isn’t working to remove the rust, try a drill with a wire wheel for tougher spots.
Always wear a mask and gloves when working with oxalic acid and keep the solution away from children and pets.
Pressure Wash the Roof
If your metal roof is not easily dented, consider pressure washing it! A strong pressure washer will easily remove loose rust from the surface.
You can rent a pressure washer if you have safe access to your roof or hire someone to wash it for you!
How to Paint a Rusty Metal Roof
Find a painting method that works best for your roof! For maximum coverage, use a paint sprayer and apply several coats of protective paint.
If you’re looking for a quick fix, consider painting over the rust. This method will work best for metal surfaces that have minimal rust or staining.
Use a Paint Sprayer
Apply new paint with a powerful paint sprayer like this to cover larger surfaces quickly! You don’t need to hire a professional for this job, just rent a paint sprayer from your local hardware store.
Try your best to apply even coats and wear protective gear while painting. Apply multiple coats to ensure that the entire surface is covered and protected.
If you can’t get your hands on a sprayer, you can also use special brushes and rollers. Using a sprayer is the fastest, and probably cheapest option if you’re looking to paint the roof yourself.
Galvanized Metal Primer
Using a galvanized metal primer can be beneficial when looking to protect your metal roof from corrosion. Galvanization is the process of applying a protective coating to steel and helps prevent rusting.
Galvanized metal primers contain high levels of zinc to prevent corrosion. The zinc will erode faster when exposed to moisture, protecting the base metal from damage.
If you are painting over a galvanized metal roof, it’s recommended to use acrylic latex paint. If the galvanized metal roof has already rusted, you’ll need to properly prepare it for a new coat of paint.
Use a pressure washer to remove any rust from the galvanized roof. Then apply metal etching primer with a paint roller and wait about three hours for the paint to dry before applying touch-ups.
Once it’s completely dry, apply a water-based primer followed by acrylic latex paint for a new-looking roof!
Coat Over the Rust
It’s possible to paint over rust without removing it first! For another DIY option, consider spraying your metal roof with a special reverse rusting paint!
Trusted paint brands like Rust-Oleum carry a rust reformer that transforms rusted metal into a paintable surface. This rust reformer will reverse the oxidation that caused the rust and help return the metal back to its original form.
Why is My Roof Rusting?
Once the metal is exposed to acidic substances, even water, it begins to oxidize. Rust is the corrosion that occurs once metals like steel have interacted with moisture.
Metal That is Prone to Rusting
Most metal roofing is made from steel, which is prone to oxidation because it contains iron. However, there are now other roofing options made from metal that are rust-resistant.
You can opt for a weathered steel roof that’s made to ionize once exposed to the elements. You can protect the metal from rusting with zinc coating and other rust-preventative primers.
It’s recommended to paint a metal roof about every 5-10 years. If your roof is exposed to harsh weather conditions, consider painting it more frequently. Regular cleaning and maintenance will help prevent further rust buildup.
How to Check for Rust
If you haven’t checked on the current condition of your roof, now might be a good time! Assess the damage yourself if you have easy roof access.
However, a professional might be able to give you a better evaluation and expert advice on how to address the situation.
Access the Roof Yourself
Find time to check out the roof yourself and access any damage on your own. Choose a warm night when the weather is calm to avoid any danger.
You’ll be able to spot rust easily with a metal roof. It will most likely appear as red corrosion typically scattered along the surface.
Be cautious and use a harness and non-slip shoes when working on your roof. If you have any doubts or concerns, always contact a professional for help!
Hire a Professional Roofing Company
You can always get an inspection from a professional roofing company if you’re concerned about any damage. They will check for rust damage, along with leaks and moisture problems.
Rust can weaken the roof’s structure, so getting an inspection can help assess whether it’s time to install a new roof!
Rent a Drone with a High-Quality Camera
If you don’t have access to your roof, you can rent or purchase a drone to do an inspection for you. You don’t have to spend a lot for a practical drone that will give you an expansive view of the roof.
If you’re into new tech, consider investing in a high-quality drone to inspect your roof routinely. You can also use the drone for recreational purposes!
How to Avoid a Rusty Roof
Although rust can seem inevitable, you can fight against oxidation with protective paints and primers. Regular upkeep and cleaning will also help keep your roof rust-free!
Rust-Resistant Paints
Look for a rust-preventative paint and primer from a trusted and recommended paint brand. Consider a 2-in-1 paint that resists rust and acts as a sealant.
Make sure to find a paint that’s high quality and safe to use on metal. Primers that contain at least 80% zinc will do a better job at preventing rust.
If you choose to use a zinc primer, it’s recommended to prepare the metal surface for the best application. You don’t want any dirt to get trapped underneath the primer, so make sure the roof is clean before application.
Protective Coating
Another option that helps prevent rust is a protective coating. Elastomeric coatings act as protective barriers that can be applied generously onto metal roofs.
These coatings work against corrosion as a sealant system. They need to be applied on a fresh surface, so make sure your roof is clean in order for the sealant to work properly.
Elastomeric coatings also come in a variety of colors! So they’re a great option if you’re looking to personalize your roof or color match it to the rest of the house.
Best Paints for a Metal Roof – Which Paints Are Safe?
There are a few paints that are safe to use on metal and work against corrosion.
Acrylic Latex Paint
Acrylic latex paint (such as this one) is a great option to use on your metal roof! Unlike most oil-based paints, acrylic latex paint is easy to clean and non-flammable.
Water-based acrylic paints are also suitable for metal roofs. Make sure to choose the same color primer and sealant to match the paint!
Acrylic latex paint is also a safe choice for tin roofs. Look closely at which paint you choose to ensure that it’s meant for metal roofs.
Oil-based Alkyd Paint
A combination of oil-based alkyd paint and galvanized metal primer can also be a safe choice for your roof. You’ll need to make sure that the paint and primer have adhered to the roof correctly for this combination to work.
Different metal paints are made for different weather environments. Find the right type of paint for your climate – whether it’s water-resistant for rainy cities or fireproof for drier areas.
How Much Does It Cost to Paint a Metal Roof?
If you’re looking to hire professionals to paint your roof, find a service that fits your budget! Roof painting is not always cheap if you want high-quality work and professional results.
Costs of Hiring Professionals
When budgeting for roof painting, prepare to spend around $2,000 for an average-sized roof. The price will depend on the square footage of the roof and your location. Larger homes will cost more to paint, especially if you have more than one roof to cover!
Professionals will clean the roof before painting and will use commercial-grade equipment that can provide great results. Using a professional company will also ensure that the primer and sealant are correctly applied so you won’t have to worry about rusting!
You also might want to first get an inspection before professional painting. An inspection can cost anywhere between $120-$250, depending on where you live. Put together a budget before hiring professionals to paint your metal roof.
Affordable Painting Solutions
You should only attempt to paint a large metal roof yourself if you have experience. Small roofs don’t always need professional painting but analyze any risks before attempting something potentially dangerous.
However, if you’re able to paint the roof yourself with a sprayer or roller, you can save yourself some money!
Final Thoughts
Painting a rusty metal roof can be a big project! You’ll need some essential tools to get you started.
Avoid harsh chemicals by creating your own cleaning solution in your kitchen with salt, vinegar, and baking soda. Dish soap and warm water can also work to loosen rust. Scrub with super fine steel wool or get a drill with a wire wheel to remove tough corrosion.
Once your metal surface is clean, you can get started on painting! It’s recommended to apply primer and paint that contain a large amount of zinc to prevent rust.
You can also apply elastomeric coatings and sealant that will provide a protective barrier between the metal and any moisture.
If you don’t have enough experience to paint your own metal roof, it’s best to contact a professional for help!
I’m struggling with what type of paint to use on galvinized metal roof. Approximately 40% of roof has surface rust. I know how to clean & etch metal roofs, I’ve used spray equipment before and know the process. I just want to use the best paint & primer to help extend the life of roof. Water base? or Oil base?