How to Clean Your Corrugated Fibreglass Roof: Tips from A Pro

Keeping your roof tidy is not an easy thing to do. Since it’s usually out of view, you’ll likely notice it when it’s too late. So, how do you clean corrugated fibreglass roofs?

Corrugated fibreglass roofs are superior and offer more benefits than alternative flat roofing materials. Also, they require much less maintenance, but that doesn’t mean they need none. 

But cleaning it is usually a lot easier than other roof types.

Here, we are going to determine how you can keep your roof in the best shape so that it can last its expected fifty years lifespan.

What Is A Corrugated Fibreglass Roof?

Typical FRP Corrugated Fiberglass Panels are made in a translucent colour of clear, green or white to allow light to flow into any building or sky lighting where you will use it. Fibreglass reinforced polymer (FRP) corrugated panels remain virtually unaffected in many chemical environments. 

These Corrugated Fiberglass panels are strong, durable, shatter-resistant and will not rot, rust, scale or have mildew. These panels are usually designed for use as roofing and siding by engineers. 

So, when the installation involves the use of a galvanized corrugated or Rib panel, the FRP panel will be used in together with the metal panels to let natural sunlight into the interior of your home. Fibreglass reinforced polymer (FRP) panels remain virtually unaffected in many chemical environments.

Why Clean A Corrugated Fibreglass Roof?

First of all, if you need to keep your roof’s “good as new” appearance, then a little bit of cleaning is necessary only occasionally. If you can safely access you, then the simplest way to clean it is by only using a bucket and a long-handled mop. 

Also, a garden hose gives the same results. If you’re planning to use a pressure washer, avoid using those that make use of hot steam as this can affect the longevity of your roof. Otherwise, any strategy should work to remove dirt, mud, and debris from the roof.

What Causes Lichen on Corrugated Fibreglass Roof?

Lichen is an organism that grows in particularly humid climates and places of constant moisture. If you’ve left your fibreglass or aluminium outside, lichen will probably begin to emerge from it. The most recommended way to go about with this is to remove the lichen immediately for prevention of spreading uncontrollably and requiring excessive time to remove. 

Never use harsh abrasives such as metal brushes or coarse steel wool to clean fibreglass, as it can scratch easily. Also, you should never use abrasive tools or alkali cleaners such as baking soda to clean fibreglass, as they will scratch the roof’s surface and damage its colour.

How to Get Rid of It?

  • Mix ¼ tsp dishwashing liquid soap with one cup of warm water and rinse the lichen with the solution and let it remain for about five minutes. It will give the solution enough time to loosen the stain.
  • Dip a toothbrush into the liquid and then gently brush the lichen stain away. Get rid of as much of the lichen stain as you can.
  • Add enough water to 2 tbsp baking soda and make a thick paste if the lichen stain is still stuck on your roof. Also, the paste should have the same consistency as toothpaste.
  • Softly brush the mixture into the lichen stain. The baking soda mixture will act as a gentle abrasive that is strong enough to remove lichen but soft enough not to cause scratches to the fibreglass.
  • Rinse the area by using clear water and wipe it thoroughly with a clean cloth.

What Causes Mould on Corrugated Fibreglass Roof?

Mould and mildew spores are found everywhere and will become visible mould growth if given the right conditions. Although mould doesn’t grow or feed directly upon the corrugated fibreglass roof, it often appears on debris and grime that’s built-up on the fibreglass. Common problem areas include bathrooms, where fibreglass tubs can quickly become covered in mould. 

Mould not only stains but may also pose a respiratory health hazard. Clean and remove mould and mildew on corrugated fibreglass roof to restore its appearance and protect your family’s health.

How to Get Rid of It?

  • Splash water onto the mould and mildew growth and brush the area with a soft-bristled brush to loosen surface debris and mould growth. Dampening the area helps minimize mould dust during the brushing process.
  • Kill the mould and mildew. Mix 1 quart of ordinary bleach with 4 quarts of warm water in a plastic bucket and pour the mixture onto the mould and mildew, thoroughly coating the fibreglass.
  • Allow the solution to sit on the mould for about 15 minutes, essentially sterilizing the area. Rinse away using fresh water to eliminate the bleach.
  • Apply a cleaning product intended explicitly designed for use on fibreglass roof. These products may be a mixture or liquid. Follow the manufacturer’s instructions, as application techniques and potency vary by product. Alternatively, dust the fibreglass with a thin layer of baking soda.
  • Scrub by using a soft sponge, vigorously scrubbing all of the exposed surfaces to remove dirt, soap, grime and body oils that may have built upon the surface of the corrugated fibreglass roof and are attracting mould. Rinse after cleaning.

What Should I Use to Clean A Corrugated Fibreglass Roof?

A fibreglass roof can look good as long as it’s clean. Luckily, cleaning it is simple. It doesn’t take long, although you’ll need to be comfortable working on the roof, high above the ground.

You’ll need the following materials:

  • Water
  • Bleach
  • Trisodium Phosphate
  • Garden sprayer
  • Hose

Should I Get A Professional to Clean My Fibreglass Roof?

Yes. Tempting as it might be to rinse away unsightly moss and algae by yourself, using a pressure washer to clean your roof can be dangerous, and also potentially damaging for your roof. 

For starters, we don’t recommend using a pressure washer without the help of professionals as while you’re standing on a ladder blowback can throw you off balance. The strong stream of water can also cause the roof shingles to loosen. Meanwhile, with asphalt shingles, the jets can strip them of the embedded granules that aid in prolonging the life of your roof.

How Do I Maintain My Corrugated Fibreglass Roof?

Aside from cleaning and coating your corrugated fibreglass roof, it needs no maintenance whatsoever. Fibreglass is a lot stronger, and a more flexible material compared to bitumen or felt. 

So, it should only require more work if you see something wrong with it.

Be sure to look out for problems like pinholes in the surface of the roof, cracks and warp. It could mean that your roof requires a replacement.

Related Questions

How Much Should A Corrugated Roof Overlap?

It can depend whether if you mean side to side or end to end. If side to side, at least one ridge. If end to end, overlap 3-6 inches.

Does Polycarbonate Roofing Block Heat?

Polycarbonate panels are resistant to any temperatures, either hot or cold, sunlight, snow, rain, and shock. It enables the panels to last for many years without fading or discolouring while also remaining damage-free of any various effects over the years.

Does Polycarbonate Roofing Block UV?

Installing polycarbonate roofing will give you ease and still allow you to enjoy the sun during summer months. Polycarbonate is a thermoplastic polymer that allows sunlight into your home but blocks out UV rays. It’s also virtually unbreakable.

What Is the Minimum Pitch for A Corrugated Roof Profile?

Corrugated roofing is excellent material on typical pitched roofs – but it has severe limitations when the pitch falls below 5 degrees. So, all roofing manufacturers recommend the 5-degree angle as the lowest slope, and they will not give any guarantees if it is installed flatter than this.

Can You Walk on Polycarbonate Roofing?

Plastic or polycarbonate roofing is usually considered non-trafficable. When it is necessary to walk on plastic sheets, you need to provide roof ladders or walk boards as a temporary crossing. Regardless of the roof type, walking on a roof can be dangerous.

What Is the Best Way to Cut Polycarbonate Roofing?

It usually comes in sheets and is relatively easy to cut. Thinner layers of polycarbonate can be scratched and snapped using a utility knife. You can use a circular saw to make straight cuts on thicker sheets. If you want to cut angles or odd shapes into your polycarbonate, you can use a jigsaw.

Is Polycarbonate Expensive?

The high price is one of the significant disadvantages of polycarbonate panels since it is much more expensive than glass and other plastics. ABS is cheaper and can offer the right solution for buyers who don’t require the ultra-toughness and heat resistance of polycarbonate panels.

Why Does Polycarbonate Turn Yellow?

The most typical way used to protect the sheet is a microscopic layer of UV polycarbonate inhibitor. When the UV attacks the polycarbonate, it changes colour and starts to turn yellow. It happens because the bonds between the polycarbonate molecules lose their strength.

We don't cut corners, We clean them.

Get in touch with us for a no-obligation quote on your cleaning needs – from residential to commercial buildings, you name it we clean it!

Leave the dirty work to us

Just Some of Our Google Reviews


Softwash Cleaning serving Melbourne, Geelong, Colac & Surf Coast and surrounding areas including: Toorak, Burwood, Werribee, Carlton, Richmond, and more. View our entire service area here.

Get A Free Quote!

Fill in the form below and we will be in touch soon with your no-obligation, free quote.