If cleaning is necessary apply a moss killer e g.
Water leaking through asbestos roof.
The difference in the level of exposure whether you have an asbestos roof or not is virtually zero.
The drainage for the roof runs down the middle to the back of the garage and the roof itself is a very shallow v shape sloping towards the central drainage.
From going inside and having a look around the roof on my side is made up of several large sheets of asbestos running towards the centre from the outside wall with some smaller pieces.
Around the area of the joint water seeps through and i can see some of the roof is damp.
The roof is leaking through the joints in what i believe is asbestos cement corrugated roofing.
Regrettably the pitch is very low and as a result when it rains hard the water ingresses and leeks into the garage.
Do not sand or scrape the cement.
Do not clean the roof unless really necessary as asbestos fibres may be released during the process.
As long as the leaking water is controlled and disposed of safely there shouldn t be any problems.
The trick is not to try to disturb or do anything with the asbestos roof yourself.
Posted by m forbes if the water is leaking through the roof the asbestos particles will be contained within the water and should therefore not be airbourne.