But the question should really be “would this have been approved if they’d asked”.

The answer to which is “no”. Had the building complied with planning requirements, retrospective permission would normally be given.

Yup. And at that point, there’s only really 3 possible outcomes

1) the rules are broken, not the house, so sort that out or
2) remedial work to bring it within an acceptable spec or balance out impact if possible, or
3) pull it down

Yup. And at that point, there’s only really 3 possible outcomes

you missed 4)Line the pockets of an expensive lawyer and take it to appeal. Again and again.

Can the council recover these costs?

Ignoring planning permission seems to be morphing into one of those socially-acceptable “non-crimes” where people consider the law to be some kind of theoretical bureaucratic inconvenience with no basis in reality.

(see also: avoiding personal taxes and most traffic offences)

wrong thread