Annexe extensions for homes in Banbury
If you live in Banbury and want more space without moving, an annexe extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in BanburyFrom £61,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsOX16
Covering Banbury
Across OX16, we can visit, measure and advise. We also work in nearby Bicester (14 miles), Witney (20 miles), Oxford (22 miles), Carterton (23 miles).
Just over the Northamptonshire border, Brackley is about 9 miles away. In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
Planning rules that apply in Banbury
In England an annexe that stays part of the household and connects to the house is assessed as an extension, but its size usually takes it beyond permitted development, so a householder application describing the ancillary use is the normal route.
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 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 an annexe extension makes sense
- Multi-generational families
- Relatives who need support close by
- Homes with a large side or rear garden
Accessibility is cheaper to design in than to retrofit. Level access, a 900 mm door width, a level-access shower and space to turn a wheelchair can all be planned into the footprint for little extra cost.
Guide prices for Banbury
For Banbury we adjust our national guide rates by ×1.12, the factor we use for South East England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Banbury: £2,240 to £4,260 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £61,500 – £77,500 | £67,000 – £84,500 | £84,000 – £106,500 |
| One-bedroom annexe 35 m² | £78,000 – £98,500 | £94,000 – £118,000 | £117,500 – £149,000 |
| Larger annexe 45 m² | £100,500 – £126,500 | £120,500 – £151,500 | £151,000 – £192,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
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 Banbury home, measure up, talk through what you want and check the planning position.
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
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Annexe extension questions answered
Who do I contract with for an annexe extension in Banbury?
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.
Do I need building regulations approval in Banbury?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Will my neighbours in Banbury 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 an annexe extension need planning permission?
Usually yes, because of its size and the way it will be used. Councils check that it stays ancillary to the main house, so the application must describe the use clearly.
Can the annexe have its own front door?
Yes, many do, but it should still connect to the main house to stay clearly part of it.
Book a free site visit in Banbury
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.