Roof Cleaning Auckland

Roof Treatment versus a roof wash

There are a couple of options for getting a roof clean, and the option that will suit you depends on your end goal. Are you planning on having the roof painted after the wash? Or do you want to wash it because it is due for a clean? 

If it is the latter, a roof treatment could be a much better option for you as it's cheaper than a roof wash. Some of the other benefits are that it's quicker and less labour intensive. It's also gentler on roofing materials and uses much less water.

If you are wanting to have it painted, then a roof wash is the best option for you.

Having your roof cleaned or a roof treatment on a regular basis will help the materials last a lot longer. When it’s not kept clean moss, algae, and atmospheric pollutants will break down the materials and make them deteriorate a lot quicker. The cost of keeping your roof clean is a lot cheaper than needing to replace or do repairs on the roof which can become very costly. When it comes to cleaning your roof we offer two options for having it cleaned.

1. Roof treatment

A roof treatment involves spraying a product onto the roof surface which kills lichen, moss and mould. The rain and sun gradually break down and remove the dead lichen, moss and mould. This process can take up to 12 months or in some cases where there is a thick covering of black mould up to 18 months. Generally results can usually be seen in the first 2 to 3 months with the moss and lichen changing colour.

You can find out more about roof treatment here such as what to do if your are on tank water.

2. Roof wash and treatment

The second option is where we use our water blasting machines to gently wash away any lichen and algae from your roof. When we do a roof wash we also apply a treatment product which kills the lichen and algae spores and stops them from returning for at least two years. Many water blasting companies don’t apply the treatment after the roof wash and the nasties quickly return and you then need to repeat having your roof washed much sooner.

 

We wash roofs of all sizes, from a 20msq shed to whopping great big commercial roofs the size of 12 rugby fields.

There are a couple of options for getting a roof clean, and the option that will suit you depends on your end goal. Are you planning on having the roof painted after the wash? Or do you want to wash it because it is due for a clean? 

If it is the latter, a roof treatment could be a much better option for you as it's cheaper than a roof wash. Some of the other benefits are that it's quicker and less labour intensive. It's also gentler on roofing materials and uses much less water.

If you are wanting to have it painted, then a roof wash is the best option for you.

Coming home to clean & sparkly kinda gives you that ‘wahoo it’s Friday’ feeling

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Roof treatment

A roof treatment involves spraying a product onto the roof surface which kills lichen, moss and mould. The rain and sun gradually break down and remove the dead lichen, moss and mould. This process can take up to 12 months. Generally, results can usually be seen in the first 2 to 3 months with the moss and lichen changing colour.

The product we apply is an industrial-strength treatment (A lot of the products for this sort of work are diluted and so do not produce the end result our product does). The product is bleach-free, non-acidic and phosphate-free.

We are VERY particular about getting a thorough coverage and apply 2 treatments when we do the treatment to ensure a good soak and thus much better results. What this means is we treat the area, wait for it to soak in and then treat it again.

We also use a very concentrated mix and even more so if there is black mould. This costs us a lot more and the chemical is not cheap however we want to do the best we can to ensure the best results possible.

You can find out more about roof treatment here such as information on what a treatment involves, the process and the benefits of a roof treatment vs a wash and what to do if you are on tank water.

Roof wash

The second option is where we use our water blasting machines to wash away any lichen, moss, mould and grime from your roof. When we do a roof wash we also apply a complementary treatment which kills the mould spores and stops them from returning for at least two years. Many water blasting companies don’t apply the treatment after the roof wash and the nasties quickly return and you then need to repeat having your roof washed much sooner.

You can find out more information here on what types of roofs are not suitable for washes, the technique we use for safety when on a roof and more.

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Keep your roof cleaner
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Talk to us to find out more about how our roof treatments

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Frequently asked questions

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I’ve had a bad experience with another company. How are you different?

We hear this a lot. What sets us apart is our consistency, communication, and commitment to care. We show up when we say we will, do what we promise (and often more), and treat your home like it’s our own. You’ll notice the difference straight away.

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How does your roof treatment actually work?

We apply a biodegradable treatment that works with the weather over time. It’s absorbed into moss, mould, and lichen, and then gradually breaks them down through sunlight and rain. No water blasting, no scrubbing, no risk of damage — just science and patience doing their job.

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When will I start seeing results?

Most customers see visible improvement within 2–3 months. For moss and lichen, full results are typically seen within 12 months. For black mould, it can take up to 18 months. This slow-release method is what makes the results last longer and keeps your roof in better condition.

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What if my roof has heavy lichen or mould?

We recommend our dual-treatment option. It includes two coats applied in one visit — the first to open up the spores, the second to penetrate deeper and kill more thoroughly. It’s only 20% more than the standard quote and well worth it for heavily affected roofs.

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Is it safe for my roof and surrounding areas?

Yes. Our treatment is biodegradable, non-corrosive, and free from harsh acids or salts. We apply it carefully using professional Venturi systems for even coverage and optimal penetration. No runoff into your garden, no damage to tiles, flashings, or fixings.

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Do I need to be home during the service?

Not at all. We just need clear access to your roof and notice of any pets or access concerns. We’ll send you updates and can provide before-and-after photos for your records.

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I am selling can I get proof that the roof has been treated?

Yes. If you're selling your home, we can provide a Completion of Works Certificate confirming the treatment has been applied. It’s a great document to pass on to your real estate agent or potential buyers for peace of mind.

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How do I know which treatment I need?

If you’re unsure, no problem — just send us a photo or let us take a look. We’ll assess your roof’s condition and give you a clear, honest recommendation with no pressure.

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What’s the difference between a roof wash and a roof treatment?

A roof wash gives you instant results. It removes visible moss, mould, grime, and lichen right away using a soft wash system. A roof treatment, on the other hand, is sprayed on and works gradually with the sun and rain over time. The roof wash delivers a dramatic visual improvement on the day, while the follow-up treatment we include helps prevent regrowth.

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Will a roof wash damage my tiles or roofing materials?

No. We use a low-pressure soft washing method — never high-pressure blasting — to safely clean your roof without cracking tiles or stripping protective coatings. It's safe for most roofing types including concrete tiles, longrun metal, and Colorsteel. Our technicians are trained to adjust their approach depending on the surface and condition of your roof.

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Why do you include a roof treatment after washing?

A wash removes the visible growth, but it doesn’t kill the spores buried deeper in the surface. That’s why we always apply a follow-up roof treatment after every wash. This helps prevent moss and mould from coming back quickly and gives you longer-lasting results from your investment.

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How long will the roof stay clean after a wash?

With the added treatment, most roofs stay looking fresh for 12 months or more. The exact timing depends on location, shade, and roof type. The treatment we apply after the wash continues working for months, helping to slow down the return of moss and mould.

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Is this a good option before painting or selling my house?

Yes, absolutely. This service is ideal for pre-sale presentation, real estate photography, open homes, and painting prep. It improves the appearance of your home instantly and can significantly boost curb appeal and buyer impressions.

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What if my roof has black mould or heavy lichen?

If your roof has severe black mould or thick lichen growth, washing is the only way to get an immediate improvement. Treatment alone won’t break it down fast enough. In these cases, we recommend a roof wash followed by our treatment to both clean and protect.

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When should you opt for a roof wash-over roof treatment?

  • If you are getting your roof painted, then it will need to be washed.
  • If you’re wanting your roof cleaned instantly and are not wanting to wait 12 months (sometimes this can be more like 6 months) then getting a roof wash would be the better option for you
  • If you have quite a lot of black mould. Sometimes a roof treatment is not always that effective on black mould. This is generally only if the mould it quite severe.

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Will water get inside my home during the wash?

In most cases, no — especially with modern windows and weather-tight joinery. But if your home has old wooden windows or perished seals, some water seepage can happen. In those cases, we recommend placing old towels or rags along the inside sills as a precaution. We always work with the grain of the house and avoid forcing water into gaps, but we can’t 100% guarantee a watertight outcome in vulnerable spots. If we notice anything concerning before we start, we’ll let you know.

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I am on tank water is a roof treatment suitable?

If you are on tank water you will need to disconnect the tanks prior to us arriving. They will need to stay disconnected until there has been 25 ml of rain. If you need help disconnecting the tanks please let us know.

The treatment product we use is 100% water-soluble. This means that the rain will wash it away even on a porous surface. To be really safe we recommend that water tanks stay disconnected until there has been 25 ml of rain.

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I have a tiled roof can you wash it without breaking tiles?

As a general rule, we don’t recommend water blasting tiles as they are often loose and water blasting can blow them off the roof which breaks them. The gentlest and cheapest option to get your roof clean is a roof treatment. If for some reason you really need to wash we will come and take a look at it and assess whether or not it is an ok candidate for a wash

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Can you wash my clear lights?

We sure can. Our approach to cleaning clear lights is to apply our wash down product, followed by a soft wash.  Lastly, we apply a slow-release product that works overtime to keep cleaning them. If the clear lights are old, unfortunately, mould gets embedded into the fibre and we are not able to remove this so often they can be far from perfect. Any mould that is sitting on the surface should clean up nicely.

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Will you need scaffolding to clean my roof?

9 times out of 10, we do not require scaffolding. Our guys will use a fall arrest system with harnesses and strops to wash the roof. They are fully trained at Working at Heights and using the fall rest systems. Here is some information about roof washes.

WE CLEAN ROOFS OF ALL SIZES, FROM A 20MSQ SHED TO WHOPPING GREAT BIG COMMERCIAL ROOFS THE SIZE OF 12 RUGBY FIELDS.
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