Single-storey rear extensions in Mangotsfield
Our design and build teams take on single-storey extensions in Mangotsfield, from the first measured survey through planning and building control to the finished room.
- Guide price in MangotsfieldFrom £21,000 inc VAT
- PlanningOften permitted development (3–4 m), or prior approval up to 6–8 m
- Build time10–16 weeks on site
- Postcode districtsBS15, BS16, BS36

How much does a single-storey extension cost in Mangotsfield?
For Mangotsfield we adjust our national guide rates by ×1.02, the factor we use for South West England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Mangotsfield: £1,780 to £3,470 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £21,000 – £25,500 | £25,000 – £32,000 | £31,500 – £42,000 |
| 4 m × 5 m 20 m² | £35,500 – £42,000 | £41,500 – £53,500 | £53,000 – £69,500 |
| 5 m × 6 m 30 m² | £53,500 – £63,000 | £62,500 – £80,000 | £79,500 – £104,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Extensions in and around Mangotsfield
Across BS15, BS16, BS36, we can visit, measure and advise. Nearby, we also take on projects in Kingswood (2 miles), Yate (5 miles), Thornbury (8 miles), Dursley (15 miles).
Keynsham, in Somerset, is roughly 5 miles from Mangotsfield and also on our list. South West homes range from terraced streets in the cities to stone cottages and bungalows in the countryside, and conservation areas are common in historic centres.
Planning rules that apply in Mangotsfield
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
When a single-storey extension makes sense
- Terraced houses that want a deeper kitchen across the full width
- Semi-detached and detached houses with a usable rear garden
- Homeowners who want open-plan living onto the garden
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Mangotsfield
How long does a single-storey extension take to build in Mangotsfield?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Do you cover all of Mangotsfield?
Yes. We cover Mangotsfield and the surrounding parts of Gloucestershire. Site visits are free and there is no obligation.
Who do I contract with for a single-storey extension in Mangotsfield?
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 much does a single-storey extension cost per square metre?
Our guide range is about £1,780 to £3,470 per m² including VAT, depending on specification. A standard-spec 4 m × 5 m room usually lands at £41,500 to £53,500 in Mangotsfield, plus design and council fees.
Flat roof or pitched roof?
Flat roofs give more headroom inside and suit lanterns and rooflights; pitched roofs can blend better with older houses. Both meet building regulations when built properly. See our flat roof and pitched roof pages for the details.
Book a free site visit in Mangotsfield
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.