How likely is my planning application to get approved in Cambridge?

Planning permission in Cambridge feels like it should be simple — but the moment you start digging, it gets complicated fast. With 13 conservation areas, 19 Article 4 directions, and over 1,600 listed buildings spread across the city, what's allowed on one street can be completely different to the next. WhatCanIBuild exists precisely because those differences are almost impossible to untangle without looking at your specific address.

Your postcode is only the starting point

CB1, CB2, CB4 — your postcode tells you almost nothing useful about your approval odds. What matters is whether your individual property sits inside a conservation area, falls under an Article 4 direction, is a listed building (or is adjacent to one), or sits on Green Belt land. Each of those layers changes the rules, sometimes dramatically. Most homeowners don't realise that two semi-detached houses on the same street can have completely different planning constraints — because the boundary of a conservation area or an Article 4 direction can cut right through a terrace.

Article 4 directions are the hidden tripwire

Cambridge has 19 Article 4 directions in force. These are local orders that remove the permitted development rights that homeowners in other parts of the country take for granted. If your property is covered by one, work you assumed was automatic — certain window changes, cladding, outbuildings — may need full planning permission instead. The problem is that most people don't know they're affected until they've already started planning. It's one of the most common reasons projects hit unexpected delays or refusals in Cambridge.

Conservation areas aren't all the same

Being inside one of Cambridge's 13 conservation areas doesn't automatically mean your project will be refused — but it does mean the council will scrutinise the impact on the character and appearance of the area far more closely. What that scrutiny looks like in practice varies considerably between areas. A rear extension that sailed through in one part of the city might face objections in another, even if the two properties look almost identical from the outside. The question isn't just whether you're in a conservation area — it's what's been approved and refused in your specific part of it.

What your neighbours' applications actually tell you

The most useful planning intelligence isn't in the rulebook — it's in what's actually been decided nearby. Similar projects on your street that were approved or refused give you a far clearer picture of your real odds than any general guide can. That's where WhatCanIBuild goes beyond what you can piece together yourself: it shows you what's been approved and refused for properties like yours in Cambridge, and what that means for your specific combination of constraints.

Cambridge's planning decisions run through the Greater Cambridge Shared Planning Service — a joint operation with South Cambridgeshire — and the typical decision window is 8 weeks, with a householder application fee of £548. But knowing the process and knowing your odds are two very different things.

WhatCanIBuild gives you the property-level picture — what constraints apply to your address, what similar projects nearby have achieved, and what your approval chances actually look like before you spend time and money on an application.