How to paint a rusty metal roof?

Painting a rusty metal roof is a project that can be undertaken alone if you have some previous experience in painting and remodeling, or else have a professional come to do it for you. so if you want to diy then you would like to know How to paint a rusty metal roof perfectly for which this post is made. if you are professional then also you will get some good wisdom and tips from here to get your paint job done at client site with utmost perfection for unexpected praises because who doesn’t like being appreciated for the work they do.

In both cases, it is necessary to know the process and required time and money that can be involved in painting a rusty metal roof.

So, how can we correctly paint a rusted roof, and what will we need to prepare for that?

Why should you paint your rusty metal roof?

Metal roofs are a great addition to houses in places that have harsh and extreme weather conditions. At the same time, these roofs are also easy to install and remodel and are inexpensive in all parts of the process.importance of metal roof painting

Metal roofing also provides an additional level of security to your house and its internal infrastructure.

Why should you repaint your metal roof if it has rusted over the years? The reasons for doing so are many.

  • Rust itself is quite harmful to the health of the inhabitants of the house as well as other organisms that might find home and recreation on your rooftop. Rust can cause respiratory diseases, allergies, and internal skin and digestive problems if individuals live in its proximity for too long.
  • Rust damages the metal in a process of drawn-out corrosion. Over a long period, this rusting process can reduce the longevity of the roofing and can cause you a full replacement if it is not stopped. Hence cleaning out the rusting as soon as it has shown itself. And coating your metal roof with a layer of paint to seal off subsequent rusting possibilities is a great way to stop this from happening.
  • A good layer of water and air-resistant paint can ward off a higher rate of rusting. It protects the metal roof from exposure to rain, snow, and wind in areas where this is a huge issue. The layer of paint can also act as an additional lubricant which speeds up the process of water and snow running off the roof and not stagnating in the corners.

How to clean and prepare a metal roof for painting?

Whether or not cleaning a metal roof that has rusted over the years is taken as a DIY project depends on the intensity and severity of the corrosion.

You can clear the rusting easily that has just begun by using intermediate skills by any individual who is not a professional.

However, a badly rusted metal roof might or might not be restored through intermediate amateur skills.

metal roof cleaning

A professional must be consulted in that situation and they will be able to tell you if a paint job will even help in this situation. Or if you should get a Full metal roof replacement and have that one painted instead.

Cleaning and preparing a rusted metal roof in its initial or middle stages of corrosion can look as follows.

Purchasing the right gear

The first step is to prepare the necessary gear for your health. Rusted surfaces can be very harmful especially if worked on for consistent periods. Eye goggles, masks, proper cleansing tools, and chemicals as well as gloves do not even cover this list. Do a lot of research and how to keep yourself while cleaning out the rust and follow those steps word by word.

Choosing chemicals to loosen up the rust

There are many home remedies and congo options that can be used to scrub off the rust from metal roofs. These include salt, vinegar, dish soap, oxalic acid solution, etc. However, when the rust has spread over large areas using these remedies can take on additional time and effort. Professional chemicals are a better option in such cases.

Choosing the correct method

If you find that the rusting has taken place over multiple layers, scrub cleaning can be preceded by a pressure wash. That will remove the top layer of the rust before you even have to begin exerting manual labor.

Start painting in the right weather

Once the cleaning process is completely done, the rusted metal roof needs to be moved on to the painting procedure as soon as possible. Leaving out the metal roof surface in changing weather, and exposing it to water and dirt again can bring back the original rusting situation.

Is it possible to paint a rusty metal roof without cleaning it?

Yes! You can easily paint over the rust on the metal roof without having to clean it first by simply coating the rusted metal roof with a layer or two of special reverse rusting paint.

Before applying this paint rust reformers can be used to create a uniform paintable surface on the rusted metal roof. These two together act as chemicals that rivers the oxidation process and bring back the original metal.

The success of these chemicals depends to a great extent on the stage of corrosion that your metal has reached. If large chunks of the metal surface have already been eaten away by the rust, obviously coating over using these chemicals is not going to bring back the original metal surface.

It is important to note that simple coating does not work on galvanized metal roof surfaces. In this case, a correct and comprehensive process of cleaning is a necessary step to painting success.

What paints are great for painting a rusty metal roof?

Surprisingly, you do not require large tonnes of expensive paint to coat over your rusty metal roof surface and make it resistant to further damage.

choosing good paint for metal roof

Simple paint types in their roofing variants can be bought and applied on the metal roof surface. Only in some especially damaged cases do expensive paints come to be required.

Acrylic paint latex-based

Water-based acrylic paint is one of the most versatile, inexpensive, and non-toxic acrylic paints.

This kind of paint will require a heavy mix of primer and an additional layer of sealant. These are both high quality and specially made for roofing purposes, to do their job well. This kind of paint is especially great for tin roofs.

Make sure you let your seller know the purpose of this paint while you are buying it so that they can suggest to you the best brands and options among the ones available.

if you are a fan of glossy finishes in outdoors then this one is for you. checkout how to make paint glossy if you want glossy shine but cant afford expensive paints.

Oil-based Alkyd paint

Oil-based paints can be a little more expensive and a bit more toxic. But they last really long and can withstand very heavy weather. If we are talking about roofs of factories, offices, or warehouses, this paint is the one to go with.

Oil-based alkyd paint does require a galvanized metal primer to work its best. These kinds of paints also require a bit more expertise to be painted on the roof. Because it is necessary to ensure that the paint and the primer have correctly stuck to the metal surface to make sure this combination will serve the purpose when it dries out.

This paint does take a longer time to dry, and painting should be chosen in a season when rains are not frequent. However, this kind of paint will work a lot better on roofs with comparatively advanced stages of corrosion.

Protective enamel paint

Protective enamel paint that is highly adhesive should be used as a top coat for good painting on galvanized metal roof surfaces. These kinds of specially designed enamel paint are resistant to environmental agents of corrosion themselves.

Just like our last choice enamel paints are oil-based and therefore not that nontoxic. Protective gear while painting with this kind of paint is necessary. it is good quality but can give dull finish after long time, so if you are into dull shades, matte textures etc. then you can choose this one.

Enamel paint will also require a long time to dry and even longer time to cure. Undertaking the painting process during suitable weather conditions is, therefore, a must.

How much will it cost to paint a rusty metal roof?

Roof painting is not a cheap business. Even if you are planning to work on it as an individual project you will require high-quality materials in great quantities.

Alternatively, if you hire a professional team of premium quality technicians to work on your roof, including the consultancy which can be added to the bill or provided for free, your average-sized roof will cost you around 2000 USD in most regions.

At the same time the larger the building and the roofing area, the more will be the bill. Suburban areas can get this facility at a comparatively cheaper rate than highly metropolitan pockets.

In cases where inspection and consultancy are not free, that alone can cost you a maximum of 250 USD.

It is quite a calculation at this point since undertaking painting jobs on metal roofs on your own as a beginner or with limited experience can result in dangerous accidents in slippery zones.

In many areas, the rusted metal roof is also accompanied by pockets of moss, dampness, and other growth. Such regions also require extra attention which a professional can give better. Hence, in many ways hiring a professional and using this time for other work can be the cleverer decision.

Step-by-step guide: Painting the metal roof

Finally, it is important to take into account how exactly you are to undertake the painting process yourself.

But then, this guide is a brief introduction to painting roofs. So make sure to do as much research as you can before starting.

roof spray painting

Clean the roof

If you have chosen to clean your roof from rust that is already existing on its surface, then definitely that is your first step. You can use chemicals like trisodium phosphate. It can penetrate the layers of rust and weaken them to an extent.

They can be scrubbed off using manual work or washes. However, these kinds of chemicals can be quite harsh on your skin, and being cautious with them while wearing protective gear is mandatory.

At all times use sprayers to spray these chemicals on the surface. And try not to touch them even with gloves on. Let the chemicals stay on for 15 minutes, and then scrub off the staining. checkout our guide on how to avoid spray painting mistakes for best finishes after paint job done.

Apply metal roof primer

We are now to apply the right primer to our roof. Any painting requires to start with a protective. And at the same time, the adhesive layer of primer helps the paint to stick on the surface for a long long period. For rusting metal roofs there are special primers.

Those are formulated in such ways as to slow down and even reverse the oxidation process of the metal surface. Follow the instructions that your primer asks you to. And you can even take some tips from friends, family, and sellers in this business.

Use rollers or paint sprayers for this step as well. The primer will take 2 days to be ready for painting. Some primers work best when mixed with the paint straight away. Hence knowing what works best in your combination is important.

Painting the roof correctly

Now it is time to start with the actual painting process. We have talked at length about the best available paints for painting rusty metal roofs in the market. The painting should only be started when the primer is completely cured and ready.

Because we are talking of roofs, choosing the kind of paint that will dry quickly is also a very important aspect. Making the correct choice can indeed be difficult. The painting process itself is simple, carried out through sprayers and rollers just like in the above steps.

Make sure you stop when you have applied a uniform coat of paint across the whole roof. Do not miss out on edges and corners.

Top coat application

If you live in an especially harsh region in terms of environment, you might want to add and final coat of paint. Go through a closed inspection on the paint job that you have only just completed. And fill out any light patches or places where you have missed a heavy enough coating.

If you really want to add a complete layer of top coat, do so while making sure that your paint is not too thick to properly dry in the expected time. Similarly, a very thick quote can cause the paint to chip off, hence the need to be careful.

To get the color according to your choice in final coat you will also need to consider weather it would dry lighter or darker based on various factors like color you choose, its viscosity, quality of paint used, number of layers applied, overall atmosphere in region etc. so choose wisely for best eye pleasing result from your paint jobs.


Painting a rusty metal roof is not that hard a process. But needs to be undertaken as soon as possible to ensure the prevention of further damage.

A complete replacement of the metal roof can cause twice or thrice that of a paint job. This being risky work, surely call in professionals if you are not very sure of handling it on your own.

metal roof painting before and after


Can we use oil-based acrylic paint for painting rusty metal roofs?

Oil-based acrylic paints can definitely be used to paint metal roofs. However, since their overall benefits are equal to that of water-based acrylic paint the latter is chosen because of its fast drying and nontoxicity properties.

Is painting a metal roof dangerous for health?

Painting metal roof is dangerous for beginners and amateurs. At times the rust and mold growing on the metal roof can cause harmful side effects to human health. Moreover, the slanting nature of metal roofs makes it a dangerous adventure.

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