I've read a lot about the pitfalls of demolition when working on a "conversion" so want to try and stay as inside the lines if possible. However, I'm struggling to find sufficient details to understand the details of what is and isn't acceptable. Here are my specifics if anyone has any information or resources you can signpost me to:
Stone barn in Wales
Full planning permission for conversion to residential (from 20 years ago - confirmed as in perpetuity because of sewage works started)
Rural, but not AONB or heritage
Likely substantial foundations work needed
Substantial repairs required to external walls
New roof structure needed (some recoverable slate)
One neighbour who is 200m+ away, plus another agricultural barn a similar distance
The building is pretty small, so optimising space is key
Ideally, a demolish and rebuild (same aesthetic and footprint, but modern construction, insulation etc) would be better performance, space efficient and cost effective, but I'm conscious that doing so can be problematic and risk the planning.
So, what is the best course of action? Is it fine if I rebuild one or two footings and walls at a time but never fully demolish, or is that a no-go? As it's full planning, non-AONB and no immediate neighbours is it less of a concern? Would a new, updated planning application for demo and rebuild likely be relatively easy or incur full blown new regs and rigour? Or should I just not risk it and just underpin and make good the existing structure and deal with the reduced space?
I'm sure "it depends" but any opinions, experience and advice appreciated!