How to Safely Remove Moss From Asbestos Roof Panels

Asbestos roof sheets are often found on garages and outbuildings. This material was once extremely popular because it was so cheap to manufacture and was very easy to work with.

The dangers of asbestos are now well known, if you are one of the many people who have these panels on your roof then our guide below will teach you how to safely demoss it and if you wish, apply a roof coating which will seal in any asbestos fibres and prevent them from being released into the enviroment.

Working with asbestos is dangerous and in addition to following the advice on this page you should check with your country's health/safety agency and follow the procedures they recommend. Always ensure you are wearing the correct protective clothing and mask.

Performing any task that creates asbestos dust should be avoided. This includes:

• Drilling
• Cutting
• Sanding
• Wire Brushing

If these tasks need to be carried out then make sure you have first dampened down the surface by pouring/spraying water on it, make sure you reapply the water as often as is required to prevent dry asbestos fibres from being released.

The following steps are how a professional roofing company would carry out such work:

• Lay scaffold planks on asbestos sheets, ensure the roof structure is strong enough to hold weight
• Spray asbestos with a significant amount of water to prevent fibre release
• Using a trowel scrape off excess moss
• Reppply water and then using a stiff broom sweep all debris of roof
• Clear out gutters of any blockages
• Fill any cracks in asbestos with a quick drying filler/sealant
• Spray sheets with a fungicide, here is a limited list of moss killers

The roof should then be left for 24 hours to fully dry out. A suitable roof coating can then be applied.

Here is a photo of a garage flat roof we recently demossed and re coated:

As you can see there is a striking difference when compared to the neighbouring roof. The coating we used is similar to this product.

Further Reading

Copper - A Natural and Organic Moss Killer
Moss Killer Chemicals
Do Roof Coatings Really Work?
The Truth About Gutter Guards
Weed Killer List