Utility and boot room extensions for homes in Chiswick
A utility room extension in Chiswick 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 ChiswickFrom £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 districtsSW13, SW14, W3, W4, W6

Is a utility room extension right for your house?
- Busy family homes
- Kitchens that have run out of space for appliances
- Houses with a side passage or small rear corner
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.
Planning and approvals in Chiswick
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Covering Chiswick
Postcode districts we cover around Chiswick include SW13, SW14, W3, W4, W6, W12. The same team covers Acton (1 mile), Barnes (1 mile), Shepherds Bush (2 miles), Notting Hill (3 miles), all within easy reach.
Across London, terraced houses with narrow side returns and tight access are the norm, which shapes everything from party wall notices to how materials reach the back garden.
How much does a utility room extension cost in Chiswick?
Prices below are for Chiswick, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Chiswick: £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.
What happens next
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 Chiswick home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions people ask about utility room extensions
Who do I contract with for a utility room extension in Chiswick?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Do I need building regulations approval in Chiswick?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does a utility room extension take to build in Chiswick?
On site, typically 6 to 10 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
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 Chiswick
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.