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

Planning permission in Cornwall feels like it should be simple — you want to build something, you apply, you get a yes or no. But the reality is that two houses on the same street can face completely different outcomes for the exact same project, and most homeowners have no idea which side of that divide they're on. Tools like WhatCanIBuild exist precisely because this stuff is far harder to unpick than it looks.

Cornwall isn't one place — it's hundreds of planning micro-environments

Cornwall Council covers an enormous area, and the planning landscape shifts dramatically across it. A homeowner in a Truro terrace faces a completely different set of constraints than someone on the rural fringes near the Tamar Valley. What looks like a routine householder application in one postcode could be a complex, contested case in another.

With 145 conservation areas spread across the county, the chances that your street falls inside one — or just outside one, where rules can still bite — are far higher than most people assume. And being in a conservation area is only the beginning. The question that actually matters is what that means for your specific project on your specific property.

The restrictions most homeowners don't know they're under

Cornwall borders or partially overlaps several Areas of Outstanding Natural Beauty, including the Cornwall, North Devon and Tamar Valley AONBs. It also contains the Cornwall and West Devon Mining Landscape World Heritage Site. Properties near those boundaries sit on what's called Article 1(5) land — where permitted development rights that homeowners elsewhere take for granted simply don't apply in the same way.

That's before you get to Article 4 directions, which can strip back permitted development rights further still in specific streets or neighbourhoods. Most homeowners don't realise these exist until they've already assumed their project doesn't need permission.

What your neighbour's approval doesn't tell you

This is where it gets uncomfortable. Even if someone on your road got permission for something similar, that doesn't mean you will. Different ages of planning history on individual plots, different distances from protected land boundaries, different constraint combinations — these all feed into how Cornwall Council assesses applications.

The £548 householder application fee is paid whether you're approved or refused. The 8-week decision clock starts ticking either way. The question worth asking before you submit isn't "do projects like mine get approved?" — it's "do projects like mine, on properties like mine, in this part of Cornwall, get approved?"

That's a much harder question. And it's the one WhatCanIBuild is built to answer — showing you what's been approved and refused near your specific address, and what the approval odds look like for your project type given your property's actual constraints.

The best way to know where you stand

Guessing is expensive. A refused application costs the same as an approved one, and the reasons for refusal are often things you could have anticipated — if you'd known what to look for. WhatCanIBuild cuts through the noise by combining your property's specific constraint profile with real local decision data, so you're not walking in blind.