A PYC tweet today:
https://www.ukgbc.org/news/government-confirms-local-authorities-can-set-energy-standards-beyond-part-l-in-nppf/
My summary:
The Government yesterday published its revised National Planning Policy Framework (NPPF).
Government said as part of the consultation: "local authorities are not restricted in their ability to require energy efficiency standards above Building Regulations".
This implies local authorities can can set energy standards beyond Part L now, but just didn't realise it.
I would love for a UK local authority to mandate something close to the Passive House standard.