Glass box extensions for homes in Swindon
From the first sketch to final sign-off, we plan and build glass extensions in Swindon and the surrounding Wiltshire area.
- Guide price in SwindonFrom £30,500 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Build time10–16 weeks on site
- Postcode districtsSN1, SN2, SN3, SN4, SN5
What is included
- Drainage details for frameless roofs
- Design with specialist glazing input
- Steel or glass beams and slim-frame glazing
- Whole-house energy calculations where needed
- Solar-control and low-energy glass specification
Local to Swindon
Across SN1, SN2, SN3, SN4, SN5, SN25, we can visit, measure and advise. We also work in nearby Calne (12 miles), Chippenham (16 miles), Devizes (18 miles), Melksham (20 miles).
Cirencester, in Gloucestershire, is roughly 14 miles from Swindon 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.
Planning and approvals in Swindon
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.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Glass extension prices in Swindon
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 Swindon: £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 |
For a figure based on your own dimensions, use our guide-price tool.
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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.
Glass extension questions answered
How long does a glass extension take to build in Swindon?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Do I need building regulations approval in Swindon?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Will my neighbours in Swindon 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 £3,060 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 Swindon.
Book a free site visit in Swindon
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.