Hi,

When I bought my house (built in 84) a few years ago the survey flagged up
that the flue was potentially made of asbestos. I didnt really worry about
this as I had no plans to disturb it. However I have just noticed quite abit
of black discoloration and im worried about it being a risk to health. Does
this look like water damage, heat damage, mould or something else? Does this
mean it is breaking down and potentially dangerous? Any advice greatly
appreciated.
https://www.homeownershub.com/img/n7