Can you start building while waiting for planning permission?

Building without planning permission is not a criminal offence in itself in England — but that's cold comfort. If your application is refused, anything you've built that needed permission is unauthorised development, and the council can serve an enforcement notice requiring alteration or demolition at your cost.

Starting early also changes how the council sees your application. Officers deciding a live application about work that's already under way may feel the process is being pre-empted, and neighbours who see builders arrive before a decision are more likely to object.

There are safer versions of getting ahead. Site preparation that doesn't constitute development — clearing, some demolition, ordering materials, agreeing contracts conditional on approval — lets you mobilise quickly once the decision lands.

If you believe your project doesn't need permission because it's permitted development, the risk profile is different — but the safe move is a Lawful Development Certificate, which gives you formal proof before you spend money on the build.

If you've already started, don't panic, but do get clarity fast: a retrospective application can regularise work, though it carries the same refusal risk as any other application — with the added cost of potentially unwinding what's built.