
Rear Extension Drawings in Kensington & Chelsea
Fixed-fee, MCIAT-chartered rear extension drawings for Kensington & Chelsea homeowners — Royal Borough of Kensington and Chelsea validation and local constraints handled from the start.
The Royal Borough of Kensington and Chelsea is one of the most design-controlled authorities in the country: a very high proportion of its grand stucco-fronted townhouses, garden-square terraces, red-brick mansion blocks and cobbled mews houses are listed or sit within conservation areas. Designations such as Kensington, Chelsea, Ladbroke (Notting Hill), Holland Park, Brompton and Earl's Court Square carry detailed material and elevation control, so applications succeed on the strength of precise, heritage-led drawings rather than standard templates.
Permitted development can rarely be assumed here. Near-comprehensive conservation-area coverage across Kensington, Chelsea, Notting Hill and South Kensington and a high density of listed buildings mean a full planning application, and often listed-building consent for internal as well as external changes, is usually required even for modest works. The borough's basements policy is nationally known for restricting new basements, generally to a single storey, and controlling excavation extent alongside a basement impact assessment. A basement or extension can still be viable, but every scheme in Holland Park, Earl's Court or World's End must be designed to policy from the outset.
We prepare Kensington & Chelsea planning and listed-building submissions that respond to the borough's townscape and its restrictive basement and conservation policies, confirming the exact designations and listing status for your address before any design begins. You get a fixed fee agreed up front, the same council-accepted drawings an architect would produce for usually around 30% less, a roughly seven-day drawing turnaround and free redraws until the council approves. Most householder applications are determined within the statutory eight weeks once validated, though listed-building and basement cases attract more consultation, so a validation-first approach matters.


Planning in Kensington & Chelsea: what to know before you apply
In Kensington & Chelsea, permitted development can rarely be assumed: near-comprehensive conservation-area coverage and a high density of listed buildings mean a full planning application — and often listed-building consent — is usually required even for modest works. The borough's basements policy generally limits new basements to a single storey and controls their extent. We confirm every constraint up front.
Typical Kensington & Chelsea housing stock
Grand stucco-fronted Victorian townhouses, garden-square terraces, red-brick mansion blocks and cobbled mews houses — a very high proportion of which are listed or sit within conservation areas.
Areas we regularly draw for in Kensington & Chelsea
Kensington · Chelsea · Notting Hill · Holland Park · Earl's Court · South Kensington · World's End
What the numbers say about Kensington & Chelsea planning decisions
These are Royal Borough of Kensington and Chelsea’s own reported figures, published by government rather than estimated by us. They are what we design against — a borough that refuses one householder application in five needs a different drawing package from one that refuses one in twenty.
Permitted development in Kensington & Chelsea
Larger householder extensions put to Royal Borough of Kensington and Chelsea under the prior-approval route, and lawful-development certificates decided, over eight quarters.
| Prior approval not requiredWent ahead without a full application | 0 |
|---|---|
| Prior approval granted | 0 |
| Prior approval refused | 0 |
| Building upwards, prior approval refused | 0 |
| Certificates of lawful development decided | 80 |
Source: Ministry of Housing, Communities and Local Government (PS1 district planning application statistics). Open Government Licence v3.0 Extracted 2026-08-16.
What removes permitted development in Kensington & Chelsea
Live entries on the national planning registers for Royal Borough of Kensington and Chelsea. Article 4 directions withdraw permitted development rights, so a project inside one needs a full application rather than prior approval. Revoked and expired entries are excluded.
| Article 4 directions in force | 84 |
|---|---|
| Areas they coverOne direction can cover many separate areas | 84 |
| Conservation areasPermitted development is already narrower inside one | 41 |
Source: MHCLG Planning Data Platform. Open Government Licence v3.0 Extracted 2026-08-16.
Rear Extension Drawings for Kensington & Chelsea homes: the package and the process
Depth is the number the application turns on, and it has to be measured from the original rear wall of the house rather than from whatever is there now. The drawings carry that dimension, the eaves and ridge heights, the position of any rooflight, and the boundary distances on both sides.
Where the scheme goes beyond the standard allowance and relies on the larger home extension route, the drawings serve a second purpose: they are what the council sends to the neighbours during the consultation. A clear, dimensioned proposed elevation answers the objection about overshadowing before it is made.
Depth is limited by the plot as much as by the rules. A long garden behind a terrace can take the full allowance, while a short one runs out before the rules do — and on a semi or detached house the same depth reads very differently from the boundary.
Do I need planning permission for a rear extension in London?
Many single-storey rear extensions qualify as permitted development, meaning no planning application is needed, provided depth, height and materials stay within set limits. That changes if your property sits in a conservation area or is subject to an Article 4 direction, both of which can remove permitted development rights across a street or borough — in that case a full householder planning application is required regardless of size.
Even where an extension qualifies, most homeowners obtain a Lawful Development Certificate to confirm that status in writing before building — useful for mortgage lenders, buyers and Building Control. We check your property against your borough's constraints before recommending a route.
How deep can a single-storey rear extension go?
Depth is the main constraint on a rear extension, and it depends on your house type and whether you use standard permitted development or the larger home extension scheme.
Permitted development
Standard permitted development allows a single-storey rear extension up to 3 metres deep for terraced and semi-detached houses, or 4 metres for detached houses, generally with eaves height limited to match or stay close to the existing house.
Larger home extension scheme
The prior-approval scheme extends this to 6 metres for terraced and semi-detached houses and 8 metres for detached houses. Your council writes to affected neighbours; if none object within the notification period, approval follows without a full planning application. If an objection is raised, the council assesses the impact on neighbouring light and outlook itself, rather than automatically refusing, so a well-considered design still has a good chance of approval.
Designing the kitchen-diner: rooflights, bi-folds and daylight
Most rear extensions exist to create one open-plan kitchen, dining and living space, so the drawing work focuses on getting light and flow right within the depth you are allowed.
- Structural opening sized for bi-fold or sliding doors across most of the rear elevation
- Rooflights or a roof lantern positioned to light the centre of the room, away from the shadow line of the main house
- Open-plan layout tested against the 45-degree rule, which protects daylight to your neighbours' windows and can limit how close a flank wall or roof comes to the boundary
- Floor build-up and threshold detail coordinated so the new floor meets the existing one without a step
| Route | When it applies | Typical fee |
|---|---|---|
| Permitted development (Lawful Development Certificate) | Depth within 3m (terraced/semi) or 4m (detached), height and materials within PD limits | PD/LDC pack ~£950–£1,450 |
| Larger home extension (prior approval) | Depth up to 6m (terraced/semi) or 8m (detached), with neighbour notification | from £1,100 |
| Full householder planning permission | Extension exceeds PD/larger-home limits, or the property is in a conservation area with an Article 4 direction | Full Planning pack ~£1,600–£2,400 |
| Planning + Building Regulations (structural) | Combined planning and construction-ready pack with structural calculations for the opening and roof | Planning + Building Regs pack ~£2,200–£3,850 |

Rear Extension Drawings across Kensington & Chelsea
Rear Extension Drawings in Kensington & Chelsea — FAQs
How much does a rear extension cost to design in London?+
Do I need an architect for a rear extension?+
How long does it take to get rear extension drawings?+
What is the 45-degree rule?+
Will I need a Party Wall Agreement for a rear extension?+
Do I need planning permission for works in Kensington & Chelsea?+
Can I build a basement in Kensington & Chelsea?+
My home is listed — what consent do I need?+
How long does the Royal Borough take to decide?+
How much do planning drawings cost in Kensington & Chelsea?+
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