What are the most common reasons planning applications get refused in Lewisham?

Getting a planning application refused in Lewisham isn't rare — and the reasons are rarely as obvious as homeowners expect. Most people assume refusal means their design was wrong or their extension was too big. But the real picture is far more complicated than that, and it often comes down to factors specific to your property, your street, and even which planning officer picks up your file. WhatCanIBuild was built to cut through exactly this kind of complexity.

It's not just about your extension — it's about your property

One of the most common mistakes Lewisham homeowners make is assuming that planning decisions are applied consistently across the borough. They're not. The development plan that guides every decision has to be applied in the context of your specific site — and that context changes dramatically depending on where you live.

Are you in one of Lewisham's conservation areas? There are over 25 of them, covering parts of SE4, SE13, SE23 and beyond. Each one carries different character appraisals, different expectations around materials and design, and different levels of scrutiny. Most homeowners don't realise that being inside a conservation area boundary — even by a few metres — can completely change what's acceptable.

And that's before you get into whether your property is listed, whether it sits in a flood zone, or whether there are any site-specific planning history issues that could affect how your application is assessed.

Article 4 directions — the rule most people have never heard of

Article 4 directions are one of the most significant and least understood reasons applications run into trouble. They allow the council to remove permitted development rights from specific areas — meaning things that would normally be allowed without permission suddenly require a full application. In Lewisham, Article 4 directions are known to apply in areas around Blackheath and Ladywell, but they can affect individual streets or even individual property types.

Here's the uncomfortable truth: most homeowners don't know whether an Article 4 direction applies to their property until they've already made assumptions about what they can build. That's a costly way to find out.

The best way to know whether your property is affected — and what that means for your specific project — is to check using WhatCanIBuild, which pulls together the constraints that apply to your address.

What's been decided nearby tells you more than any rule

Planning decisions in Lewisham aren't made in a vacuum. Officers look at what's been approved and refused on nearby properties — and that local precedent can work for you or against you depending on the history of your street.

A run of refusals for loft conversions in your road? That's a pattern that matters. A neighbour who got permission for something similar two years ago? That matters too. But you won't find that context in any general guide to planning rules. It's buried in the application history of your specific area.

This is where most articles stop — they explain the categories of risk without telling you which ones apply to your property. WhatCanIBuild goes further, showing you what's been approved and refused nearby, what that suggests about your approval odds, and how your property's specific combination of constraints shapes your chances.