Roof Cleaning

Roof Cleaning Methods: Low-Pressure Washing vs. Scraping

When it comes to cleaning roofs, there are two main methods used: low-pressure washing and manual scraping. Both methods are effective at removing moss, algae, and lichen, and both involve applying a biocide treatment afterward to prevent regrowth. However, the choice between these methods depends on the type of roof and its condition.

At our company, we care about ensuring that your roof is well looked after and not damaged in the cleaning process. That’s why we assess each roof individually and choose the safest and most effective method for long-lasting results.

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Low-Pressure Washing

Low-pressure washing uses a controlled water flow combined with a cleaning solution to gently remove dirt, algae, and organic growth from the roof. This method is ideal for roofs that can handle moisture without the risk of damage, such as tiled roofs in good condition.

  • Instant Results – This method provides immediate visual improvement, as the dirt and growth are washed away on the spot.
  • Gentle on the Roof – Since it uses low pressure, there’s no risk of damaging the tiles.
  • Biocide Treatment – A biocide is applied afterward to kill any remaining spores and prevent moss and algae from returning.

However, not all roofs are suitable for low-pressure washing. Older, fragile, or porous roofs might absorb too much water, leading to potential damage.

Manual Roof Scraping with Compressed Air

For some roofs, particularly older ones or those with heavy moss buildup, scraping is the best option. This method involves manually removing moss with a roof scraper before applying the biocide treatment.


We also use a new technique involving compressed air, which gently blows the moss off the roof instead of aggressively scraping it. This keeps the roof safe while still achieving excellent results.

  • Better for Fragile Roofs – Scraping combined with compressed air avoids excessive water exposure and prevents damage to delicate or aged tiles.
  • Innovative & Gentle Approach – Using compressed air is a new, safer technique that reduces stress on the roof while effectively removing moss.
  • Long-Term Effectiveness – While the results aren’t always instant (as it takes time for the biocide to work and fully clear any remaining discoloration), the roof remains moss-free for a long period.
  • Biocide Treatment is Key – Even though scraping removes the bulk of the moss, applying biocide afterward ensures that any leftover spores are killed, preventing regrowth.

Safe, Professional, and Insured Service

We take safety and professionalism seriously, which is why we never step foot on your roof. Walking on tiles can cause unnecessary damage, so we work safely from mobile scaffolding or a cherry picker, ensuring that your roof remains intact throughout the process.

  • Trained & Insured – Our team is fully trained and insured, so you can have peace of mind knowing your property is in safe hands.
  • No Risk of Tile Damage – By working from professional access equipment, we eliminate the risks associated with walking on fragile tiles.
  • Health & Safety First – We follow strict safety protocols to protect both our team and your property.

Our Commitment to Roof Safety

We understand that every roof is different, and using the wrong cleaning method can cause unnecessary damage. That’s why we carefully assess your roof before beginning any work. Whether we use low-pressure washing or scraping with compressed air, you can be confident that we will choose the safest and most effective approach.


Regardless of the method used, applying a biocide treatment afterward is essential to prolong the results and prevent regrowth, ensuring a clean and well-maintained roof for years to come.

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