[DamonHD]

Making better use og roof-tops generally is a win as far as environmentalists are concerned; NIMBYs/BANANAs may complain however.

Not that I see any intrinsic beauty in concrete titles or roofing felt. Even clay tiles and slates I suspect are just something we have gotten used to.

In all cases they are a financial and embodied energy and financial cost as-is, and PV can turn them into something positive.