Cleaning Roof Tiles

Roof tiles can quickly become infested with mould, algae, and other organisms that create ugly marks, and lead to expensive damage. A roof should be cleaned roughly every two years, and due to the danger involved, it’s highly recommended to hire a trained professional. But if you’re set on doing the job yourself, and are confident in your ability to keep yourself safe, this article will explain how to clean your roof tiles, covering everything that you need.

1. Get the right safety equipment

Our bones are best left unbroken, and you’ll want to satisfy this universal principle while cleaning your roof. To do so, you’ll need the right equipment, including:

  • Non-slip shoes that have good traction, so that you can tread safely while cleaning (no rubber thongs, please)
  • A sturdy ladder for getting up to the roof
  • A safety harness that attaches to a secured anchor point on the roof

For the sake of your safety, it’s best not to skimp on equipment.

As the job gets underway, you’ll find that you need to consistently retrieve equipment from the ground, which adds extra time and work to the job. You’ll save yourself a lot of time if you have a partner who can pass you the equipment you need, when you need it. They’ll also have a wider view of the roof, and can help to direct your efforts as you clean.

2. Check thoroughly for faults

One of the most effective ways to clean a roof is with a pressure washer, which produces a lot of water that could leak into your property. Before firing up the washer, inspect the roof thoroughly for cracked or broken tiles, damaged roof flashings, cracked window edges or siding, broken caulk, cracked sarking, and whether the roof ridge is properly intact. Without an inspection of every fixture on the roof, water can leak into your property, which can lead to mould, stains, bad smells, and a tempting dinner invitation for termites.

3. Use a pressure washer

While it’s possible to manually scrub each tile clean with a rag, you’ll save yourself a lot of time by using a pressure washer, which produces a high-pressure jet of water that will blast your roof tiles clean.

All you’ll need to use in the pressure washer is water—no roof tile cleaning chemicals or products are needed for this step. You’ll need to experiment with the washer’s settings to find the most suitable amount of pressure, just enough that you can see the tiles are being cleaned, but not so high that you might break the tiles or cause leaks, which can happen regardless of the roof being free of damage. Ultimately, a professional roof cleaner will know the right amount of pressure to use.

When you’re walking across the roof, place your feet on the sturdier area in-between each tile, to reduce the chance of slipping. If there’s large patches of moss or plant life, don’t count on them for good grip.

To ensure that you’re always standing on a dry patch of roof, start the job at the top left corner, clean your way down to the bottom in a thin strip, and then repeat the process until you’ve covered the entire roof. If there’s stubborn moss or other plants that the pressure washer is failing to remove, you’ll need to use an anti-moss treatment to get rid of them (more on this in the next section).

If you don’t have a pressure washer, you can buy one for around $100 to $500, or alternatively, rent one from a company such as Kennards.

4. Apply anti-moss spray

For the tenacious plantlife that wants nothing more than to stay attached to your roof, an anti-moss (or fungicide) treatment will help to persuade it otherwise. The treatment is added to your pressure washer, and then sprayed across the roof using the same safe method as before, ensuring that the roof is completely dry before you start. You may also want to wear rubber gloves for this step, to prevent the chemicals from touching your skin.

If you have a rainwater tank, you’ll want to temporarily divert the pipe to prevent it from becoming decontaminated. Similarly, if any guttering pipes flow out into green areas of your garden, you’ll want to redirect them to protect your precious plantlife.

Once you’ve covered the entire roof with anti-moss spray, give it a few minutes to sink in, and rinse it off again with clean water. You should find that previously stubborn plant life has become compliant, washing away more easily.

Regular cleaning of your roof tiles is necessary to keep it looking schmick, and to extend its lifespan. If taking on the job yourself seems difficult and dangerous, there’s roof cleaning professionals at hand who have the equipment and experience needed for the operation. Professional roof cleaners charge anywhere between $38 to $80 p/hr, depending on the material of your roof, the complexity of the job, and the location. While you can certainly do the job yourself, you’ll need to take every precaution necessary to protect yourself.