Utility and boot room extensions in Isleworth
Our design and build teams take on utility room extensions in Isleworth, from the first measured survey through planning and building control to the finished room.
- Guide price in IsleworthFrom £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 districtsTW1, TW3, TW4, TW5, TW7
Local to Isleworth
Postcode districts we cover around Isleworth include TW1, TW3, TW4, TW5, TW7, TW8. Nearby, we also take on projects in Hounslow (1 mile), Heston (2 miles), Richmond (2 miles), Southall (3 miles).
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.
What is included
- Built-in storage or space ready for your units
- Back door and a hard-wearing floor
- Waste and water connections
- Design around appliances, sink and storage
- Ventilation for a tumble dryer
Planning and approvals in Isleworth
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.
The planning position for a specific Isleworth address depends on its history and any designations, which is why we check it at the first visit.
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).
How much does a utility room extension cost in Isleworth?
These guide figures apply our London adjustment (×1.3) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Isleworth: £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.
From first visit to completion
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Isleworth
Do I need building regulations approval in Isleworth?
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 Isleworth?
On site, typically 6 to 10 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
Will my neighbours in Isleworth 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.
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 Isleworth
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.