How to Clean Rust on Roofs

How to Clean Rust on Roofs

Although rust on roofs is more common on metal, it can also affect some shingle roofs. Rust stains on shingle roofs aren’t from your roofing material though – not unless you have shingles that contain metal at least. Most often, rust stain on shingle roofs are from a nearby metal object, such as your chimney flashing or metal drainage pipes. When these structures start to rust, the brownish red color can bleed onto the surrounding areas of your shingle roof.

Regardless of whether you have a metal or shingle roof, rust stains are unsightly and will take away from your home’s curb appeal. Rust is a more common problem on metal roofs, as the roofing itself can develop rusty spots over time. Especially in Florida, where humid weather conditions worsen the rust on your roof. The fact that the ocean releases salt water particles into the air, means that metal objects are even more prone to rust near the coastline.

What Causes Rust?

The scientific term for rust is iron oxide (III). The term “oxide” is commonly used in chemistry to refer to a compound consisting of oxygen and another chemical element. Thus, iron oxide is formed when iron atoms bond with oxygen atoms, but what causes this to happen?

The Science Behind Rust

Before looking at how iron bonds with oxygen, consider carbon and oxygen.

Carbon dioxide is a naturally occurring compound consisting of a single atom of carbon and two oxygen atoms. As a compound, carbon dioxide naturally occurs in the air we breathe and is even expelled from our lungs when we exhale.

However, carbon atoms can combine with oxygen atoms to form other compounds as well. Carbon monoxide is an example of this, as it consists of one carbon atom and one oxygen atom.

But on an atomic level, even small differences in composition have a large impact on the compound that’s formed. Carbon monoxide is also a compound consisting of carbon and oxygen. But unlike carbon monoxide, only one atom of oxygen is present in each molecule rather than two. As a result, carbon monoxide is hazardous to breathe in and can even lead to death if too much is inhaled.

Similarly, rust is a chemical compound consisting of two iron atoms bonded with three oxygen atoms. Just like with carbon, iron can bond with oxygen in different ways. For example, iron oxide can consist of a single atom of iron and oxygen each, but this isn’t rust. When this happens, the resulting compound is referred to as iron oxide (II), but this isn’t rust. The only ratio of iron to oxygen atoms that will produce rust is two iron atoms to three oxygen atoms, forming iron oxide (III).

The reason why rust naturally is because iron and oxygen have opposite charges. This causes oxygen and iron atoms to form bonds to neutralize their respective charges.

Why Does Your Roof Rust?

As you might’ve guessed, your metal roof or chimney flashing contains iron. When the iron atoms in your roof bond with oxygen atoms, it causes a process called oxidation. As the iron oxidizes, the metal in the roof converts to iron oxide (III), or rust.

The process of rust formation happens specifically when water is present. Water helps iron to react with oxygen, which is why it’s necessary. Salt water further accelerates rust formation. But metal objects don’t have to be submerged in water for rust to form. Water vapor present in the air can be enough to facilitate rusting.

Seeing as Florida is by the ocean, a lot of water particles are present in the air. Salt water vapor is also common in areas right next to the shore, meaning rust is a persisting problem in the sunshine state.

How to Clean Rust on Your Roof

To clean rust from your roof, you can book a professional roof cleaning from a Florida roof cleaner. Your roof cleaning service will most likely use a solution of oxalic acid to clean the rust from your roof. They’ll also use special equipment, such as pressure washing machines to thoroughly clean your roof and leave it looking spotless.

When dealing with rust stains on your roof, professional help is a must. The chemicals and equipment used to remove rust stains from your roof can be dangerous if you don’t know how to work with them.

Some organic rust converters are available on the market. These products are safer to use than acid, as they simply convert the rust into other harmful chemicals by means of chemical reaction. However, rust converters won’t necessarily be effective at removing all the staining on your roof, as it’s most effective on areas that are highly rusted. If certain areas on your roof are very rusted, a rust converter might be a good choice to reduce the problem though.

Repaint Your Rusty Roof after Cleaning It

While cleaning rust stains from your roof will already improve its appearance, it won’t prevent your roof from rusting again. Once your roof is clean, you’ll need to investigate it to find the areas where the rust is forming. These areas will need to be treated to prevent rust from forming again.

To get rid of the rust once and for all, you’ll need to use a wire brush or sanding tool to remove the rust. After thoroughly cleaning your roof and all the rusted spot, it must be repainted as soon as possible to minimize exposure to air and moisture.

If you don’t repaint a metal roof after cleaning it, your roof will look better for a while. But once rust starts to form again, it will likely be at a more rapid pace. By cleaning the roof, you’ll remove some paint and exposing the rusted areas more. Because of this, repainting with a water resistant, weather proof coating is essential.

Before applying the paint you chose for your metal roof, you must treat it with a steel primer. Applying a primer will is one of the best ways to prevent rust from forming again.

How Rust on Roofs Can Be Prevented

It’s better to prevent rust from forming on your roof than to treat it once it forms. New metal roofs and chimney flashings are often covered in a rust resistant coating. Even slate and asphalt shingles are coated for protection. Over time, this rust resistant coating will wear off, however.

For metal roofs, the best way to prevent rust is to ensure the roof is always coated in water resistant coating. Be sure the repaint your roof every few years. If the paint starts to look old and faded, your roof could benefit from repainting.

When you do maintenance on your roof, don’t forget to check every component f your roof. It can be easy to forget to check nails or rivets and focus only on the roofing panels, but rusty nails can cause rust stains to bleed from the affected area. Any roofing components that are rusted must either be replaced or cleaned and treated for rust.

If you a chimney flashing or similar metal fixture on your roof, you can also have it cleaned so that you can treat it for rust. When applying primer and paint to a chimney, opt for high heat paints. The chimney area is often exposed to high temperatures which normal finishes can’t withstand. For the best results, your paint and primer should be rated to withstand approximately 250 degrees Fahrenheit. A paint that’s rated for 250 degrees might not require a primer if you’re using it on your chimney, so you can ask your local hardware store assistance for help in choosing the right product.


Maintaining your metal roof is the best way of preventing rust. Even with the best maintenance, the coastal weather can still take its toll on your roof. Working with expert roof cleaners and maintenance contractors can help you restore your roof to its former beauty!

how to clean roof shingles

How to Clean Roof Shingles: Best Methods to Protect Your Roof

Roof shingles aren’t all the same. Different types of roof shingles are made with a variety of materials. However, when it comes to cleaning your roof shingles, the cleaning methods you use will be similar regardless of what material your shingles are made from. It’s important to know how to clean roof shingles the right way. Even if you plan on hiring a roof cleaning service, learning about proper roof cleaning techniques will help you choose the right people for the job.

What Are Roof Shingles?

Not all homeowners are familiar with different roofing materials. Perhaps you aren’t even sure whether you have a shingle roof. Luckily shingle roofs are easy to spot.

Shingles are used as a roofing material for sloped roofs, so if your roof is flat, you can already know it’s not made with shingles.

Although shingle roofing is the most common choice of material in the U.S, sloped roofs can also be built with other materials. Other popular materials for sloped roofing include:

  • Corrugated metal
  • Thatching
  • Roof tiles

Corrugated metal and thatching are easy to distinguish from shingles. Metal roofs don’t consist of individual tiles or shingles. Instead, each section of the roof will consist of one large sheet of metal. Thatching is also easy to tell apart, as thatched roofs are made from straw or reeds.

roof tiles look similar to shingles, but they're not entirely the sameThe only roofing material that can be a bit tricky to distinguish from shingles is tiles. With both shingles and roofing tiles, the roof will have a tiled appearance. The roof will consist of various tiles or shingles that overlap at the edges. Because of this, many people consider roof tiles to be a form of shingle. What distinguishes roof tiles from regular shingles is the material they’re made from.

In America, most roof shingles are made from asphalt. Occasionally, shingles can also be made from slate or even wood. Roof tiles are specifically made from clay. It’s easy to see the difference between asphalt shingles and clay tiles if you know what to look for.

Clay roof tiles are normally much thicker than shingles, creating a more textured look where the tiles overlap. Shingles are normally much thinner than clay tiles, so the areas where asphalt shingles overlap isn’t always as noticeable.

Luckily maintenance and cleaning are similar for clay tile and asphalt shingle roofs.

Should You Pressure Wash Your Roof?

One of the most popular and widely used methods for cleaning roofs is pressure washing. There are some advantages to pressure washing, seeing as it’s a quick way to clean a roof. The powerful pressure washer beams also deep clean the roof surface, getting rid of a lot of algae spores and tough stains.

Unfortunately, there are also some disadvantages to cleaning a roof with a pressure cleaner. Although roof shingles are made to withstand extreme weather conditions and powerful gusts of wind, they aren’t necessarily made to withstand pressure washing.

The beams from most pressure washers are powerful enough to cause injury – any beam that powerful can certainly damage your roof as well. Many people claim that pressure washing blasts away roof shingle granules, stripping away the longevity of your roof one wash at a time.

Another problem with pressure washing is your roofing warranty. If your roof is new, pressure washing could possibly cause you to lose the warranty on your shingles. Check with the supplier where you bought your shingles before having your roof pressure washed.

Is Pressure Washing a Roof Bad?

While the disadvantages of pressure washing seem disastrous, pressure washing a roof might not be all bad. Many homeowner’s insurance companies will require you to pressure clean your roof regularly if you want to claim for any roof damage. This is because removing moss and algae from your roof increases its lifespan and prevents leaks.

As a homeowner, it’s your responsibility to decide what’s best for your home. While not everyone agrees that pressure washing is a good way to clean a roof, many people who oppose pressure washing advise not cleaning a roof altogether, insisting that moss and algae growths are simply a cosmetic problem. Others suggest washing roofs with lower pressure, such as with a garden hose or garden sprayer.

How to Clean Roof Shingles without Damaging Your Roof

The safest way to clean your roof is to clean it at a low pressure. Many roof cleaning services focus on cleaning roofs at low pressures. They do this either by using special pressure washing equipment, or by foregoing power cleaning altogether in favor of using a garden hose or sprayer.

To avoid damaging your roof during cleaning, it’s best to hire a roof cleaning expert. There are several benefits to hiring a professional roof cleaning service:

  • You’ll stay safe and prevent serious injury from falling
  • Experts are trained and equipped to stay safe on the job
  • Trained professionals deliver impeccable results while protecting the integrity of your roofing system
  • A reputable company will have the necessary insurance to protect your best interests

Keeping safe and staying out of harm’s way is one of the most important reasons to hire professionals. Walking on a sloped roof that’s wet and possibly even slippery with soap can easily lead to a fall.

According to statistics released by The Center for Construction Research and Training in 2013, falls from roofs accounted for one-third of the fall fatalities in the construction industry between 1992-2009. That’s a significant amount, considering that constructors are legally required to adhere to safety standards that aim at preventing such deaths.

Considering how many deaths occur in the professional sector, it should be clear to see why cleaning your own roof is a risky undertaking.

That said, when hiring a professional, you still want assurance that they’ll do the job the right way. There are some things you can ask to ensure you’re getting a good service.

Questions to Ask Your Roof Cleaning Service

The best way to ensure your roof cleaning service will clean your roof properly is to ask the right questions. Knowing what questions to ask will help you choose a company that will clean your roof in a way that’s safe and effective. Some of the questions you should ask include:

  • What insurance does your company have? In most states, contractors such as roof cleaners are required to have at least some insurance. Ideally, you want to work with a company that has both worker’s compensation cover and general or professional liability insurance. At the very least, a company should have worker’s compensation cover, as it’s a legal requirement in most states.
  • What roof cleaning methods do you use? Simply ask the question without mentioning any concerns you have with pressure washing. A good company will mention that they use soft cleaning methods that aren’t damaging to your roof when answering this question.
  • What cleaning detergents do you use? Most companies will use bleach, as it kills of algae and moss. However, some detergents can be harmful to your garden, so ask what precautions they’ll take to protect your garden.
  • What safety precautions will you take? Even if a company has the necessary insurance, you don’t want someone to get injured while cleaning your roof. Safety precautions are an important part of professionalism in any industry.

Stay away from any company that doesn’t have insurance. Roof cleaning services are required to have insurance in most states, so companies without insurance usually operate illegally. As a result, you might be held accountable if an incident occurs and one of the workers get injured on the job. Additionally, an uninsured cleaner won’t be able to compensate you for any damages to your property as a result of their negligence.

Cleaning your roof keeps it looking brand new. In most cases, getting your roof cleaned on a regular basis will also extend its lifespan. When it comes to how to clean roof shingles, it’s best to hire a professional to ensure your roof doesn’t get damaged during the cleaning process. Just be sure to hire a reputable company that will offer you a premium service at a competitive price.