Glass box extensions across Clevedon
Our design and build teams take on glass extensions in Clevedon, from the first measured survey through planning and building control to the finished room.
- Guide price in ClevedonFrom £30,500 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Build time10–16 weeks on site
- Postcode districtsBS21

Working in Clevedon
Site visits are available across Clevedon (BS21). Nearby, we also take on projects in Nailsea (4 miles), Portishead (5 miles), Weston-super-Mare (8 miles), Burnham-on-Sea (15 miles).
Kingswood, in Gloucestershire, is roughly 15 miles from Clevedon and also on our list. 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.
Guide prices for Clevedon
Prices below are for Clevedon, 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 Clevedon: £3,060 to £5,920 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2 m × 4 m 8 m² | £30,500 – £37,000 | £30,500 – £38,500 | £35,000 – £47,500 |
| 3 m × 4 m 12 m² | £36,500 – £44,500 | £42,500 – £54,000 | £52,500 – £71,000 |
| 3 m × 6 m 18 m² | £55,000 – £66,500 | £64,000 – £81,000 | £78,500 – £106,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Planning and approvals in Clevedon
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.
The planning position for a specific Clevedon address depends on its history and any designations, which is why we check it at the first visit.
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.
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).
Who a glass extension suits
- Small infill spaces and side returns
- Period and listed-style houses where a light touch is wanted
- Garden-facing dining rooms
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Common questions in Clevedon
Will my neighbours in Clevedon 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.
Do you cover all of Clevedon?
Yes. We cover Clevedon and the surrounding parts of Somerset. Site visits are free and there is no obligation.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Clevedon, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
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 £3,060 to £5,920 per m² including VAT, because structural glass is made to order. A 12 m² standard-spec glass extension is typically £42,500 to £54,000 in Clevedon.
Book a free site visit in Clevedon
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.