Chelsea pitched roof extensions, designed and built
Thinking about a pitched roof extension for your Chelsea home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in ChelseaFrom £28,500 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsSW1W, SW1X, SW3, SW5, SW7
Extensions in and around Chelsea
Site visits are available across Chelsea (SW1W, SW1X, SW3, SW5, SW7, SW10). Neighbouring towns we cover include Battersea (1 mile), Fulham (1 mile), Notting Hill (2 miles), Shepherds Bush (3 miles).
East Molesey, in Surrey, is roughly 10 miles from Chelsea and also on our list. London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
Guide prices for Chelsea
Prices below are for Chelsea, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Chelsea: £2,400 to £4,550 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £28,500 – £34,000 | £33,500 – £43,000 | £42,500 – £55,000 |
| 4 m × 5 m 20 m² | £48,000 – £56,000 | £55,500 – £71,500 | £71,500 – £91,000 |
| 5 m × 6 m 30 m² | £72,000 – £84,000 | £83,500 – £107,500 | £107,000 – £136,500 |
For a figure based on your own dimensions, use our guide-price tool.
What we take care of
- Vaulted ceilings or flat ceilings with storage above
- Lead or proprietary flashings to the main wall
- Roof windows positioned for light and ventilation
- Roof design matched to the existing pitch and tiles
- Insulation to current building regulations
Do I need planning permission in Chelsea?
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
We visit your Chelsea home, measure up, talk through what you want and check the planning position.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions people ask about pitched roof extensions
Do I need building regulations approval in Chelsea?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do you cover all of Chelsea?
Yes. We cover Chelsea and the surrounding parts of Greater London. Site visits are free and there is no obligation.
How long does a pitched roof extension take to build in Chelsea?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
Can I have a vaulted ceiling?
Yes. A vaulted ceiling with roof windows is one of the main reasons to choose a pitched roof. It needs insulation between and under the rafters to meet the building regulations.
How much does a pitched roof extension cost?
Our guide range is about £2,400 to £4,550 per m² including VAT, a little more than a flat roof because of the roof structure and tiles.
Book a free site visit in Chelsea
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.