Utility and boot room extensions across Somerset
Planning a utility room extension in Somerset? We survey the house, work out the planning route, draw the design and build it, so you deal with one team from the first visit to the completion certificate.
- Guide priceFrom £14,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Towns covered11
- Site visitFree, no obligation

Towns in Somerset
When a utility room extension makes sense
- Busy family homes
- Houses with a side passage or small rear corner
- Kitchens that have run out of space for appliances
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.
Utility room extension prices in Somerset
These guide figures apply our South West England adjustment (×1.02) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Somerset: £1,940 to £3,570 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2 m × 2.5 m 5 m² | £14,000 – £17,000 | £14,000 – £18,000 | £14,000 – £18,000 |
| 2.5 m × 3.2 m 8 m² | £15,500 – £18,500 | £18,000 – £23,000 | £22,500 – £29,000 |
| 3 m × 3.6 m 11 m² | £21,000 – £25,500 | £25,000 – £31,500 | £31,000 – £39,500 |
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.
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.
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).
Extensions in and around Somerset
Towns we cover in Somerset include Bath, Weston-super-Mare, Taunton, Yeovil, Bridgwater, Portishead, Frome, Burnham-on-Sea. In the South West, local stone, render and brick vary from town to town, so matching materials is a big part of designing an extension that looks right.
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Utility room extension questions answered
How long does a utility room extension take to build in Somerset?
On site, typically 6 to 10 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
Do I need building regulations approval in Somerset?
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 Somerset, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Can a utility have a toilet?
Yes, space permitting. A WC needs drainage and extraction, which we plan into the design.
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.
Book a free site visit in Somerset
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.