Chelsea utility room extensions, designed and built
A utility room extension in Chelsea starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in ChelseaFrom £18,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time6–10 weeks on site
- Postcode districtsSW1W, SW1X, SW3, SW5, SW7

Included in a typical project
- Ventilation for a tumble dryer
- Design around appliances, sink and storage
- Built-in storage or space ready for your units
- Back door and a hard-wearing floor
- Waste and water connections
A good utility works like a back-of-house corridor: in from the garden, boots off, coats on hooks, washing on the way through. We plan the door positions so it doesn't become another room to walk around.
Guide prices for Chelsea
For Chelsea we adjust our national guide rates by ×1.3, the factor we use for London. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Chelsea: £2,470 to £4,550 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2 m × 2.5 m 5 m² | £18,000 – £22,000 | £18,000 – £23,000 | £18,000 – £23,000 |
| 2.5 m × 3.2 m 8 m² | £19,500 – £23,500 | £23,000 – £29,500 | £29,000 – £36,500 |
| 3 m × 3.6 m 11 m² | £27,000 – £32,500 | £32,000 – £40,500 | £40,000 – £50,500 |
Try the guide-price tool to see a range for your own size and finish.
Will the council need to approve it?
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.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Covering 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).
Just over the Surrey border, East Molesey is about 10 miles away. In London, space is at a premium and gardens are often short, so side returns, wraparounds and carefully planned rear extensions tend to make the most of every metre.
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions people ask about utility room extensions
Will my neighbours in Chelsea be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
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.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Chelsea, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Does a utility extension need planning permission?
Often not, if it is single storey and within permitted development limits. We check this for your property.
Can a utility have a toilet?
Yes, space permitting. A WC needs drainage and extraction, which we plan into the design.
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.