Thanks for your replies to this thread - all read with great interest. I
have also spoken to a few people 'in the known' in person or by phone.

The solution which apppeals to me most at the moment is a rubber membrane
covering, with hard foam (eg Kingspan) insulation underneath to make it
either a 'hot roof', or on top to make it an 'upside down' roof. However,
when I receive the quotes and see all the noughts on the end, I may not be
quite so enthusiastic!

I would be interested in hearing the views of anyone with experience of EPDM
rubber membrane roof coverings, such as Hertalan and Prelasti.

Thanks and bye from Rick in Wakefield