Wraparound extensions for homes in Keynsham
From the first sketch to final sign-off, we plan and build wraparound extensions in Keynsham and the surrounding Somerset area.
- Guide price in KeynshamFrom £36,500 inc VAT
- PlanningUsually a householder application
- Build time14–20 weeks on site
- Postcode districtsBS31
Is a wraparound extension right for your house?
- Terraced houses that want the largest ground floor possible
- Families who want kitchen, dining and living in one space
- Semi-detached houses with a side passage
Planning and approvals in Keynsham
In England a wraparound extension is assessed as both a side and a rear extension, and the combination usually falls outside permitted development, so most need a householder planning application (£548 from 1 April 2026).
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
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).
How much does a wraparound extension cost in Keynsham?
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 Keynsham: £2,040 to £3,770 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Compact L-shape 18 m² | £36,500 – £44,500 | £42,000 – £53,500 | £53,000 – £68,000 |
| Medium L-shape 25 m² | £51,000 – £61,500 | £58,500 – £74,000 | £73,500 – £94,500 |
| Large L-shape 32 m² | £65,000 – £78,500 | £75,000 – £95,000 | £94,500 – £121,000 |
Try the guide-price tool to see a range for your own size and finish.
Covering Keynsham
Across BS31, we can visit, measure and advise. Neighbouring towns we cover include Bath (6 miles), Nailsea (11 miles), Portishead (13 miles), Frome (15 miles).
Just over the Gloucestershire border, Kingswood is about 3 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.
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Your questions about a wraparound extension in Keynsham
Who do I contract with for a wraparound extension in Keynsham?
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.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Keynsham, 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 long does a wraparound extension take to build in Keynsham?
On site, typically 14 to 20 weeks once approvals are in place. Before that, allow 8–16 weeks design and approvals.
Will I need to move a drain?
Often. Side returns frequently contain a manhole or a shared drain. Building near or over a public sewer needs the water company’s consent in England and Wales, which we arrange.
Do wraparound extensions need planning permission?
Usually, yes. In England the side element counts as a side extension and the rear element as a rear extension, and the combination normally falls outside permitted development. A householder application costs £548 in England from 1 April 2026.
Book a free site visit in Keynsham
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.