Are you considering having your roof cleaned?
Doing your research to compare steam cleaning (hot pressure washing / jet washing) vs manual roof brushing / scraping as methods for cleaning your roof?
You are in the right place as The Roof Moss Cleaners are genuine experts in roof cleaning. We have cleaned thousands of roofs all over the South East in the past decade.
There are two prevalent methods for removing moss and debris from a domestic roof:
- Steam cleaning
- Manual scraping
Each approach has its own advantages and disadvantages while both methods are followed up with a biocide roof treatment to give longevity to your roof clean.
What is steam cleaning?
Steam cleaning is a term used in the roof cleaning industry to describe hot water, low pressure jet washing of a roof.
The term “steam cleaning” is not factually correct as steam is not being used to clean, hot water is.
Steam is produced because of the water temperature, giving the visual effect of steam cleaning.
Steam cleaning is perfectly safe to use for certain types of roofs such as natural slate or machine manufactured clay roof tiles.
The smooth, natural surface of these tiles allow for a perfect cleaning process with very little risk of damage to the tiles or slates.
Steam cleaning can be carried out using a pressure washer, boiler and telescopic cleaning poles with a low pressure, turbo nozzle attached.
The turbo nozzle creates a vortex with the hot water pumped through the boiler, up the telescopic pole by the pressure washer – all at a very low pressure of around 50-60 bar.
The same pressure is used by DOFF steam cleaning equipment which is accredited for use in cleaning historic buildings by Historic England.
What is manual scraping and treating?
Manual roof moss scraping and treating is the process of removing moss from a roof by hand, then treating the roof to prevent future moss growth for years to come.
Leading roof tile manufacturer Marley actually state “Scraping moss off the roof – Moss can be scraped off with hand tools, but this must be performed with caution to avoid damaging roof tiles and slates.”
A professional roof cleaner will use telescopic poles with scraper heads that are specifically shaped for each tile profile.
Telescopic poles used in roof cleaning have interchangeable heads enabling the cleaning specialists to change from a profile scraping head to a wire brush quickly and easily.
Scraper heads and wire brushes allow for 99% of roof moss to be physically removed.
Once the moss has been removed a Biocide is applied to the roof tiles. We only use Pureseal’s Bac Clear Pro, which is the only licenced roof wash Biocide product in the UK. (Licenced by the HSE and registered on the COPR Database No 10878).
Biocide kills living organic growth on the roof, such as moss spores, lithen, algae and any other living organism. Over the course of 6-9 months the surface dirt is washed away from the roof tiles by the biocide roof wash.
We offer a 3 year moss free guarantee – giving you peace of mind in your roof cleaning investment. Biocide treatment is applied after manual scraping and after steam cleaning of roof tiles.
Roof Cleaning Methods – Cost Comparison
Steam cleaning is normally the cheaper method of roof cleaning for larger detached properties while manual scraping and treating is the cheaper option for smaller properties.
Access is also a cost factor to consider. A cherry picker is often required for a manual scrape of a clay or slate roof but is not always required for a steam clean. Steam cleaning can be carried out from a further distance using telescopic poles than manual scraping.
Every property is unique and the cost of roof cleaning is unique to each property.
Pros and cons of Steam Cleaning a Roof
Pro’s
- Gives an instant clean
- Faster and cheaper than manual scraping over large areas of roof
- Can get a perfect clean without the use of chemicals (Environmentally friendly)
- Kills moss and algae spores with high temperature cleaning
- Lowest possible risk of damaging tiles (non contact cleaning)
- Includes cleaning of Gutters, Soffits and Fascias free of charge
Cons:
- Inherent risk of water ingress if roof construction is poor or failing.
- Unsuitable for concrete roof tile cleaning
- Painted roofs should not be cleaned using steam
- Messier cleaning process than manual scraping / treating (Don’t worry we are experts at leaving your property clean!)
Pros and cons of Manual Scraping and Treating a Roof
Pro’s
- Precise and controlled cleaning – reducing the risk of damage to any delicate roofing materials
- No risk of water ingress into your property
- Suitable for all roof types
- More cost effective on smaller rooftops
- Prepares the roof for long term biocide protection
Cons:
- Does not give an instant “clean”
- Labour intensive and time consuming
- Reliance upon Biocide to cleanse the roof tiles.
- Higher risk of damage to your tiles if your cleaners are inexperienced (Our team leaders all have a minimum of 5 years roof cleaning experience)
- Gutter, Soffit and Fascia cleaning is not normally included.
Factors To Consider When Choosing A Roof Cleaning Method
Factors to consider when choosing a roof cleaning method include the roof material, cost and the need for an instant clean.
Steam cleaning will always give an instant clean, even for concrete tiles – however the process is highly likely to damage the coating of the concrete tiles.
Manufactured natural Clay and slate tiles are perfectly suitable for steam cleaning.
Cost is an obvious factor but if you have concrete tiles any savings on roof steam cleaning compared to manual cleaning will be diminished in years to come. The longevity of the tiles will be much reduced due to the damage caused to the concrete tiles in the cleaning process.
| Roof Tile Type | Recommended Cleaning Method |
| Traditional Handmade Clay Tiles | Manual to prevent damage to blown clay tiles |
| Modern Manufactured Natural Clay Tiles | Steam cleaning or Scraping / Treatment |
| Natural Roof Slate | Steam cleaning or Scraping / Treatment |
| Composite Roofing Slates | Scrape Only – No Treatment or Steam Cleaning |
| Concrete Tiles | Manual Scraping & Treatment Only |