Thank you Ian, I value your views.
No separate approval for solar panels. Permission is to replace existing ply/asphalt roof (was once asbestos) with profiled metal & insulated. (Might do this as SIPS?)
LPA has't asked for a structural report which is noteworthy. Planning Conditions relate to soil contamination tests, drainage, bin store & parking. Nothing in relation to the building.
Plans & proposed new elevation designs approved. Existing 4 outer walls of fairly weak horizontal timber cladding, and permission is for new vertical cladding of enhanced quality, all around, ergo replacement, to upgrade to residential standards supporting the barn aesthetic.
There's no proposal to construct outside the existing ridge line/envelope at all.
Nuance?!