OK, thanks for that. so other than paint, what sealant can I use? Is there a spray on sealer that is suitable for fibro?

Thanks for the feedback. The problem is not so much the outside now. The inside is not lined and the back of the sheets are exposed. It has been like…

Hi all.
I have an old timber frame single garage. It is clad with some form of sheeting which I guess has asbestos in it due to its age. I extended…