Glass box extensions in Oxfordshire
A glass extension in Oxfordshire starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide priceFrom £33,500 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Towns covered10
- Site visitFree, no obligation
Working in Oxfordshire
Towns we cover in Oxfordshire include Oxford, Banbury, Abingdon, Bicester, Didcot, Witney, Thame, Henley-on-Thames. 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 and approvals in Oxfordshire
In England a glazed or orangery-style extension follows the same size limits as any single-storey rear extension: 3 m or 4 m without an application, or up to 6 m and 8 m through prior approval. Building regulations limit glazing to about a quarter of the new floor area plus the openings it replaces, unless whole-house calculations show the design still performs.
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 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).
Included in a typical project
- Solar-control and low-energy glass specification
- Whole-house energy calculations where needed
- Design with specialist glazing input
- Drainage details for frameless roofs
- Steel or glass beams and slim-frame glazing
Solar gain is the risk. We specify solar-control glass, plan for opening vents or sliding panels, and avoid fully glazed roofs on south-facing extensions unless shading is included.
Guide prices for Oxfordshire
Prices below are for Oxfordshire, using the South East England factor of ×1.12. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Oxfordshire: £3,360 to £6,500 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2 m × 4 m 8 m² | £33,500 – £40,500 | £33,500 – £42,500 | £38,500 – £52,000 |
| 3 m × 4 m 12 m² | £40,000 – £48,500 | £47,000 – £59,500 | £57,500 – £78,000 |
| 3 m × 6 m 18 m² | £60,000 – £73,000 | £70,500 – £89,000 | £86,500 – £117,000 |
Try the guide-price tool to see a range for your own size and finish.
Our process, step by step
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 Oxfordshire home, measure up, talk through what you want and check the planning position.
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
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Glass extension questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Oxfordshire, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in Oxfordshire?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Will my neighbours in Oxfordshire 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.
Are glass extensions cold in winter?
Modern double or triple glazing with warm-edge spacers and underfloor heating keeps them comfortable. They are not as warm as a solid room, and we explain the trade-off honestly.
How much does a glass extension cost?
Our guide range is about £3,360 to £6,500 per m² including VAT, because structural glass is made to order. A 12 m² standard-spec glass extension is typically £47,000 to £59,500 in Oxfordshire.
Book a free site visit in Oxfordshire
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.