Do I need planning permission in Hammersmith & Fulham?

Planning permission in Hammersmith & Fulham isn't a simple yes or no — and that's the problem. What's allowed on one street may be completely off the table two doors down, and most homeowners don't realise this until they're already committed to a project. WhatCanIBuild exists precisely for this: to cut through the borough-level complexity and tell you what actually applies to your address.

Permitted development isn't always permitted

Most homeowners start from a reasonable assumption: if a project is small enough, it probably doesn't need planning permission. And nationally, that's broadly true — permitted development rights exist for a reason. But in Hammersmith & Fulham, those rights are stripped back in ways that catch people off guard.

Article 4 directions are the mechanism. They can remove permitted development rights from specific streets, specific property types, or specific kinds of work — and they don't come with obvious signposting. You won't know you're affected unless you check your specific address. Assuming you're fine because your neighbour did something similar is a gamble that regularly goes wrong.

Conservation areas change the calculation entirely

Hammersmith & Fulham has a high concentration of conservation areas, and they cover more ground than most residents expect. Being inside one doesn't automatically mean everything needs permission — but it changes the rules significantly, and the specifics depend on exactly where you are and what you're proposing.

What trips people up is thinking that knowing you're in a conservation area is enough. It isn't. The question is what that actually means for your project, your property, and the particular changes you're planning. That's a much harder question to answer — and it's where most DIY research falls short.

What your neighbours did probably doesn't apply to you

This is one of the most common mistakes. You see an extension on your street, assume the same rules apply to you, and proceed accordingly. But planning decisions are made on a property-by-property basis. Different plot sizes, different distances to boundaries, different conservation area designations, different Article 4 coverage — any of these can produce completely different outcomes for houses that look identical from the street.

The best way to understand what's actually been approved nearby — and why — is to look at the real decision data for your area. WhatCanIBuild shows you what similar projects on your street and in your postcode have actually achieved, not just the generic rules that may or may not apply to your situation.

What this means for your project

If you're planning any kind of work — an extension, a loft conversion, a new outbuilding, changes to your roof or windows — the answer to whether you need permission isn't in a general guide. It's in the specific combination of constraints that apply to your property.

Hammersmith & Fulham's typical decision time is 8 weeks, and a householder application costs £258. Getting it wrong means delays, enforcement risk, and potential problems when you come to sell. The best way to know where you stand before you commit is to check your address with WhatCanIBuild — it tells you not just what constraints exist, but what they've meant in practice for projects like yours.