Roly wrote:

Any advice or suggestions ?

Thanks for all the comments.

Well it's not hard to see that the consensus is that foam isn't the
favoured solution.

The lady in question has found builders and tradesmen to be unreliable,
being happy to quote for a job, but not always coming back to actually
carry out work - at least not for small jobs.

So would she be better to get a roofing contractor or a builder in ?

She lives in a very small town, so there aren't that many tradesmen
around to offer a range of quotes. Are there any crafty ways to ensure
that the quote is realistic and the work is done well ?