When it comes to removing moss and algae from metal roofs there are two options you can consider.
The first is simply to have the affected areas on the roof treatment 'Benzalkonium Chloride" and let the moss, algae and organic matter die and fall away on its own.
How long will this take?
The organic matter will die within 1-2 weeks to die and then after a few months will fall away on its own. Light green algae will disappear within 1-2 weeks but heavier more developed organic growths such as moss and lichen can take a few months to erode away from the weather. This is popular options as it leaves no chance of paint work being damaged especially on older roofs where the paint is starting to fail, often due to the moss and lichen itself damaging the paint with its roots growing into the paint. If sprayed yearly/ every 18-24 months with the roof treatment then the organic matter will not grow back and your roof will maintain its paint integrity for longer, allowing for an increased life span of the roof. This is definitely the most cost effective way to maintenance your roofs life span.
The second option is to carefully water blast the moss and lichen from the roof before spraying with a treatment. Customers often choose this approach as it produces same day results which is usually preferred with customers. This method however, depends on how developed the organic matter is and whether it will bring up paint when removed by force. This is a discussion we have with customers and the right choice is made to ensure they get outcome they expect while protecting the quality of the existing paint as much as possible. We want all our customers to be satisfied with the results and will always suggest what is best for them. Either way, a treatment should always be added to the roof to prevent rapid-regrowth.
Houses Collecting Tank Water
If your house is collecting rain fall in a tank then the tanks will need to be manually disconnected for around 2-3 weeks in order prevent contaminated of drinking water. After a few good heavy rain falls the excess treatment will be washed away and the organic matter will be dying and on its way out.
Give us a call to discuss options and quotes 0800243662
Here is a job we completed recently, removing the moss and lichen the same day and treating to prevent regrowth.
Before After
