Retrospective planning applications in London

How the enforcement time limit works

Councils cannot act for ever. Since changes made by the Levelling-up and Regeneration Act 2023, the time limit for enforcement against most unauthorised building works is 10 years from substantial completion.

That does not mean you should wait. A council that has opened a file can move quickly, and a buyer's solicitor will usually ask for evidence either way. Delay also makes it harder to evidence what was built and when.

If your work is older than the limit, a Lawful Development Certificate may be the better answer than a planning application. The Lawful Development Certificate page explains how proof of lawfulness is drawn up.

What the council can do once enforcement has started

The council has the power to decline to determine a retrospective application that covers matters already set out in an enforcement notice issued before the application. So acting before a notice arrives keeps every option open.

National policy also treats deliberate breaches seriously. Evidence that unauthorised development was intentional should be given substantial weight. We say this plainly to owners at the start, because an honest account of how the work happened is part of a credible application.

If the council refuses, an appeal is still open: you have 12 weeks from the date on the decision notice to lodge a householder appeal. Our planning appeals service picks up from there.

What drawings a retrospective application needs

A retrospective application needs the same drawings as a normal one, with one difference: they show the building as it really is. A measured survey is therefore the first step. We record the extension, the roof, the windows, the levels and the boundary.

Drawing from the survey, rather than from the builder's sketches, matters because officers visit. If the drawings disagree with what they see on site, the application loses credibility and the council may open an investigation into the discrepancy itself.

We then prepare existing, as-built and, where the council is likely to ask for changes, proposed amended drawings. Our measured building survey work supplies the base.

Officers often ask how the work differs from any earlier approval, so we add a one-page schedule of differences to the set, listing each change against the approved drawings.

Fee and decision period

The council's householder fee is £548 for alterations or extensions to a single dwelling in the current table. That goes to the council, on top of our own charge, and the exact sum is confirmed from the live fee table in your quote.

The council has 8 weeks to decide a non-major application unless you agree an extension. That is a statutory period, not a promise about any one decision.

Our own price is fixed once the free check of constraints is done. It depends on the size of the work and whether amendments are likely.

Making the building acceptable

Sometimes the honest advice is that part of the work will not be accepted as built. A rear dormer may be too large, or a side extension too close to the boundary. In that case we propose the smallest change that answers the council's concern, and draw it as an amendment so you can see the cost of the fix against the cost of refusal.

A building that has been completed also needs Building Regulations sign-off. Where that was never obtained, our building regulations drawings team assembles the paperwork for regularising it. Should the planning officer ask for amendments, we redraw free of charge.

Honesty helps here. A covering letter that says plainly what was built, when and why, reads better to an officer than a defence that the drawings later contradict.