Andrew formulated the question :
On 13/01/2019 19:28, Harry Bloomfield wrote:
was thinking very hard :
I have a large shed (far too large to consider re-roofing) which has a
corrugated asbestos-cement roof that probably dates from the 60s. It's in
quite good condition but there are a couple of cracks and one 4" hole
where a pipe used to pass through.
It seems the repair options are either Flashband (+primer), an EPDM patch,
making a GRP patch, covering with a bit of corrugated roofing, or using
galvanised mesh and cement. What else should I be thinking of? Any
recommendations?

Box section, corrugated painted metal roof as a replacement, it is not that
expensive.

Drips condensation during cold weather though.

As does asbestos. Steel can be fixed by either buying the insulated
version, or adding insulation.