Extension in Kensington and Chelsea
Do you need planning permission for a single-storey extension in Kensington and Chelsea? Here is what the permitted development rules say, how Royal Borough of Kensington and Chelsea’s designations change them, and what decides an application, grounded in the official guidance and quoted verbatim.
Do you need planning permission for a single-storey extension in Kensington and Chelsea?
Many single-storey rear extensions are permitted development under Class A, within set limits on depth, height and how much of the garden they cover, so no planning application is needed. In Kensington and Chelsea this matters: the borough has 41 conservation areas and 84 Article 4 directions, and inside those the permitted development route narrows or is removed, so a single-storey extension can need a full application where it would not two streets away.
The starting point
Many single-storey rear extensions are permitted development under Class A, within set limits on depth, height and how much of the garden they cover, so no planning application is needed.
“This provides permitted development rights for the enlargement, improvement or other alteration of a house.”PD technical guidance, Class A · full text in the library → · official source →
How Kensington and Chelsea’s designations apply
| Designation in Kensington and Chelsea | Published |
|---|---|
| Conservation areas | 41 |
| Article 4 directions (PD removed) | 84 |
| Listed building outlines | 2,609 |
Because extension depends on permitted development rights restricted on article 2(3) land, the conservation areas above are decisive: inside one, expect to need a full application. Counts are read live from planning.data.gov.uk; your report checks them against your exact address.
What Kensington and Chelsea weighs
Where an application is needed, design does the deciding: depth against the neighbouring rear walls, loss of light, roof form, and materials against the parent building.
As a London borough, Royal Borough of Kensington and Chelsea also decides against the London Plan 2021 (the strategic policy layer for all 33 boroughs), alongside national policy and its own Local Plan.
See a single-storey extension in a real report
London’s most common project: a kitchen extension behind a Victorian terrace in a conservation area with an Article 4 direction. 262 nearby decisions, 81% approved.
Get a planning report for your Kensington and Chelsea address
A Planning Policy report reads the designations on your exact Kensington and Chelsea address, quotes the Royal Borough of Kensington and Chelsea and national policies that apply to a single-storey extension, and (on Pro) shows decided applications nearby with outcomes.