Home office extensions across Thornbury
Planning a home office extension in Thornbury? 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 price in ThornburyFrom £16,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time8–12 weeks on site
- Postcode districtsBS35
Covering Thornbury
Postcode districts we cover around Thornbury include BS35. We also work in nearby Yate (7 miles), Mangotsfield (8 miles), Kingswood (10 miles), Dursley (10 miles).
For homes towards Somerset, Portishead is around 12 miles away. 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 should I budget for a home office extension in Thornbury?
Prices below are for Thornbury, using the South West England factor of ×1.02. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Thornbury: £1,890 to £3,470 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 3.2 m 8 m² | £16,000 – £19,500 | £17,500 – £22,500 | £22,000 – £28,000 |
| 3 m × 3.6 m 11 m² | £20,500 – £25,000 | £24,000 – £30,500 | £30,000 – £38,500 |
| 3 m × 5 m 15 m² | £28,000 – £34,000 | £32,500 – £41,500 | £41,000 – £52,500 |
Try the guide-price tool to see a range for your own size and finish.
Included in a typical project
- Sound insulation to the adjoining rooms
- Layout for desk, storage and video calls
- Data cabling and plenty of sockets
- Heating or cooling sized for the room
- Window and rooflight placement to avoid screen glare
Do I need planning permission in Thornbury?
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 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).
How the project works
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 Thornbury 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.
Your questions about a home office extension in Thornbury
Who do I contract with for a home office extension in Thornbury?
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.
How long does a home office extension take to build in Thornbury?
On site, typically 8 to 12 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Thornbury, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How much does a home office extension cost?
Our guide range is about £1,890 to £3,470 per m² including VAT. An 11 m² standard-spec office is typically £24,000 to £30,500 in Thornbury.
Can I claim the cost against tax?
Building work on your home is not normally an allowable business expense, and claiming it can have capital gains tax effects. Speak to an accountant before assuming any tax relief.
Book a free site visit in Thornbury
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.