Simon Hawthorne wrote:

I need to put some insulation up there - but don't want to waste money
by putting something down only to find it unsuitable when we come to
convert.

What should I use? Kingspan/celotex? Can I cut it to fit the varying
widths I'd need? If this is the best solution, how do you fit it?

You could go with the insulate the roof option, as has been suggested.
If you want to go for the more conventional approach between the ceiling
joists, then use something fireproof like Rockwool since you can then
re-use it later.

Can I also ask about the loft conversion - woudl the rafters as they
are support another couple of rooms - or would the whole rafter thing

Not a chance....

need upgrading (by an expert!)

Upgrading yes, although you will need someone who knows what they are
doing to design the stucture, implementation may not require much
expertise beyond basic capentry and common sense.


--
Cheers,

John.

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