We use all methods to roof clean and we can advise the best when doing a roof survey / quotation. Having years of experience and first hand experience we know what roofs are okay to steam / light pressure wash and we know where some tiles may be delicate and require a soft wash. We have washed tiles up to 80 years old or so and have never had any major problems. 

Light pressure wash is self explanatory, the pressure used is low and it removes all organic growth (moss, lichen, algae etc) instantly, following the PW a biocide is applied every time to prevent any regrowth for years. 

Soft washing is using zero pressure, we scrape around 95% of the moss off using one of our scraping tools on our extension poles (all from the scaffold tower) – once as much moss as possible is removed a strong biocide is applied to do the rest and naturally remove the rest and clean up the roof using Mother Nature. A great alternative to any delicate roofs or roofs with no felt / backing. 

Q Clean are fully insured to protect both us and customer of any accidental damage but of course we don’t plan on any of that! We have never had to use it this far!