In reply to arch:
> Do you know any decent builders ?? Shouldn't be out of the realms of a good builder to do an loft conversion. But a lot depends on what type of roof trusses and supporting walls you've got as to whether it's a big job or a really big job.
Totally agree, also depending on the layout of doors and rooms on the lower floors, it might entail extra work and cost to meet fire regs. As you need a clear exit from attic space to outside door, that doesn't involve enter any open space on the lower floors, there are get outs with escape ladders, a balcony style loft, fire doors etc.. minefield of regs, as said read up what you can first then use BC.