The Algae Invasion: Protecting Your Roof from Unwanted Green Growth

Roof algae and mold can affect all types of roofs in a variety of climates. If left untreated, algae and mold on the roof can not only appear unsightly but also cause a host of problems for the homeowner.

In this post, we’ll give you the information you need to first identify mold and algae growth on roof. Then we’ll take you through the different types of roof algae and mold and explain the difference between moss and algae on roof and other related issues.

This article will also explain the importance of removing algae from roof and why it’s more than just an eyesore. You’ll also learn about roof algae removal to keep your roof and home safe from damage.

Finally, we’ll explain how to prevent mold and algae from growing on your roof in the first place, to prevent it from getting a hold on your property. Once you reach the end of our latest post, you’ll have learnt useful information to keep your roof in great condition and your home looking good.

What is that green (or black) stuff? Understanding roof algae and mold

If you’ve noticed black, grey or green growth on your roof, this could be roof algae and mold or another type of vegetation. Let’s understand the difference between algae, lichen and moss to give you a clear picture of what you’re dealing with.

Black roof algae

Maybe you’ve spotted dark, dirt-like streaks on your roof, growing flat against its surface. This is most likely to be black roof algae, also known as gloeocapsa magma.

It thrives in damp environments and is often found on the north-facing side of your roof, which dries out less well than other surfaces. You may notice that the pattern of algae follows the path of water down your roof.

Because black algae on roof can mimic the appearance of dirt, it is often misidentified by homeowners. However, if it’s left untreated it can permanently stain your roof tiles and because it traps moisture, harm the integrity of your roof.

Mold and mildew

Unlike algae and moss, mold is not a healthy plant. Roof mold can appear as black or brown blotches, or slimy, foul-smelling accumulations. Mold can occur in places where your roof has absorbed water.

Mildew is similar in that it grows on damp surfaces and can cause health problems. Mildew can take a powdery appearance and have many different shades, ranging from black to pink. All types of roof bacteria pose different threats to your roof, home, and health.

Mold resembles black roof algae but has a slimy texture. It may also have an offensive smell. Meanwhile, mildew—a type of mold—has a powdery appearance and comes in a variety of shades, including black, white and pink.

Lichen

It is a combination of algae and fungi, appearing as light green spots or patches on your roof.

This type of growth attaches very securely to your shingles and is hard to remove. It can even take off the top layer of your shingles and leave a permanent mark.

Like algae, lichen grows well in damp conditions such as north-facing roofs or shaded areas.

Moss

If you’ve spotted lots of green stuff on roof, it could be that you have a moss problem. Moss is sometimes mistaken for green algae on roof but has a distinct appearance, taking the form of green, fuzzy patches.

A thick carpet of moss will stop moisture escaping from the surface of your roof and can result in additional issues such as algae and lichen growth as it traps spore in its spongy fibers.

The unseen dangers: Why algae and mold are more than an eyesore

Whatever type of growth you’re dealing with, it’s important to understand that the damage it can cause is more than skin-deep.

As well as looking unsightly and impacting on your property’s curb appeal, algae on roof shingles can cause lasting damage if left unattended. Here’s what could happen as a result:

• Permanent staining. Black algae, in particular, can leave indelible stains on your roof tiles. The same is true of lichen, which attaches incredibly tightly to shingles, making it hard to remove.
• Damage to roof shingles. Any growth on your roof shingles can cause damage. This may be because it traps moisture, leaving your shingles permanently damp, or because, particularly in the case of lichen, it may take a layer of material away when it is removed.
• Damage to the underlying roof structure. Algae and other growths trap moisture onto your roof’s surface. This can penetrate the underlying structure of your roof, rotting wood and other materials and contributing to leaks and damage inside your home.
• Damage to other structures. Algae spores are wind-borne, which means they can affect other buildings too. This means you might also end up with algae roof issues on sheds or carports or other structures on your property.
• Increased energy bills. Algae, moss and other growths can trap heat inside your home, making your air conditioning work harder and increasing the cost of keeping your home comfortable.
• Risk to your health. Algae on shingles may be associated with mold or mildew, which also grow readily in damp environments. Mold and mildew spores can cause respiratory problems, trigger allergies and make conditions such as asthma worse. Inhaling mold spores can also lead to a serious condition called mold-related hypersensitivity pneumonitis causing coughing and shortness of breath.

Taking back your roof: Effective algae removal strategies

To remove algae from roof, it’s best to call in a professional team who are used to working at heights and using solutions designed to clean algae, mold, mildew, lichen and moss safely.

If you’re looking for a reputable roofing specialist serving Massachusetts or New England, reach out to the team at Plum ProExteriors.

We’ll start with a thorough inspection of your roof to identify the type of issue you’re facing, whether that’s algae or another growth.

We’ll then clean algae off roof using the most appropriate treatment method, which could be removal by hand and/or a bleach-based cleaning solution.

While we’re up there, we’ll also check for damage to your gutters or roofing and recommend solutions to fix these using our professional roofing services.

The Plum ProExteriors team can also advise on preventing further growth of algae, mold and other vegetation, to ensure that your roof is kept in great condition for a long time to come.

Remember, it’s always best to treat algae and mold and other growths sooner rather than later, before they stain or damage your roof. With hundreds of completed projects and many years of experience under our belt, Plum ProExteriors are the experts you can count on!

Prevention is key: stopping algae and mold before it starts

Algae on roof shingles can be prevented by adopting a care and maintenance routine for your roof:

• Clean algae off roof. Keep your roof free of algae, mold and other growths like moss and lichen to prevent spores spreading and making the problem worse. Get your roof cleaned by a professional company like Plum ProExteriors to minimize the spread of algae and mold.
• Fit algae-resistant shingles. These contain zinc or copper granules that inhibit algae or mold growth. Have them fitted near the ridge line at regular intervals for maximum impact. You can also fix metal strips at these locations. When it rains, metal ions are released downwards, creating an inhospitable environment for algae and mold growth.
• Use algaecide. This is a solution that resists algae growth. When you apply it to your roof’s surface regularly, you can extend the time between regular maintenance sessions.
• Clean your gutters. Removing deposits of algae, moss or other vegetation from your gutters helps halt their spread across your roof and onto other structures. Clean your gutters twice a year to remove debris and help keep your roof protected from growths and water damage.
• Cut back overhanging vegetation. Algae, moss, lichen, mold and mildew thrive in damp, shady environments. If you have overhanging tree branches or other vegetation that contribute to a damp climate where growths can thrive, get them cut back.
• Keep your attic ventilated. When your attic isn’t properly ventilated, moisture can become trapped under the roof’s surface. This provides the perfect environment in which algae, mold and other vegetation can grow.
• Pay special attention to the north-facing side of your roof. This area of your roof receives the least sunlight and so is more likely to be a damp breeding ground for algae, moss and lichen.
• Replace damaged shingles. Inspect your tile shingles regularly to check for damage. You are more likely to find algae on shingles that have been cracked or damaged, leading to water ingress.
• Book a yearly roof inspection. To keep your roof in optimum condition, book an annual inspection. This will help to identify any signs of damp that could lead to algae and mold growth or clues that it has already taken a hold.

Call Plum ProExteriors, roofing experts at your service!

When you spot algae growth on roof, you’ll need to act fast. Aside from looking unsightly, algae on roof tiles can indicate problems with damp that could threaten the integrity of your roof.

Reach out to the team at Plum ProExteriors—we’re the roofing experts for Massachusetts and New England at your service! Our professional team will guide you through the process of cleaning your roof and checking for any underlying issues. We’ve been in the business for years and are dedicated to helping homeowners keep their most important asset in the best possible condition.

Give us a call today and let us give you a free, no obligation quotation for roof algae removal and repairs.