What is a glazed extension?

A glazed or contemporary extension uses large panes of glass, slim aluminium frames and modern cladding to create a bright room that contrasts with the original house. Frameless corners, structural glass roofs and minimal sliding doors are typical features.
How much does a glazed extension cost in Weston-super-Mare?
In Weston-super-Mare, a glazed extension typically costs £2,850–£4,300 per m² of floor area, including VAT at 20% (standard rate). For a typical 18 m² project that is roughly £51,500–£77,500. Prices in the South West sit near the national average for this kind of work, and the range for Weston-super-Mare reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (13 m²) | £37,000–£56,000 |
| Typical project (18 m²) | £51,500–£77,500 |
| Larger project (25 m²) | £71,000–£107,500 |
| Rate per m² | £2,850–£4,300 |
The biggest cost drivers are:
- Cladding material
- Overheating and energy design
- Lighting and finishes
- Glazing size, specification and lead time
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a glazed extension in Weston-super-Mare?
The approval route for Weston-super-Mare is set by planning law in England. In England a single-storey rear extension is often permitted development: broadly up to 3 metres deep on a semi-detached or terraced house and 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary, and covering no more than half the garden. The larger home extension scheme allows up to 6 or 8 metres if you notify the council first and neighbours have a chance to comment. In conservation areas, National Parks and National Landscapes the larger home extension route, side extensions and cladding are not permitted development. Flats and houses whose rights have been removed need a planning application, and listed buildings need listed building consent.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
On a typical glazed extension we handle:
- Energy and overheating calculations where needed
- Electrics, heating and finishes
- Foundations, walls and insulated roof
- Large-format sliding doors and fixed glazing
- Contemporary design and planning drawings
- Cladding or render finish
How long does it take?
Allow 12 to 16 weeks on site; glazing lead times can be 6 to 10 weeks. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Weston-super-Mare
The South West mixes stone and render cottages with post-war and newer estates, and local materials matter more here when matching an extension.
From BS23 outwards, we take on projects throughout Weston-super-Mare and the surrounding parts of Somerset.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about glazed extensions in Weston-super-Mare
Is triple glazing necessary?
Not always. High-performance double glazing can meet the standards; triple glazing helps in exposed locations.
How much does a glazed extension cost in Weston-super-Mare?
In Weston-super-Mare, a glazed extension typically costs £2,850–£4,300 per m² of floor area, including VAT at 20% (standard rate). A typical 18 m² project comes to roughly £51,500–£77,500. Your fixed price depends on the survey and drawings.
How long do large glass panels take to arrive?
Often 6 to 10 weeks after final measurements, so we order them as soon as the structure is built.
Do you build glazed extensions in Weston-super-Mare?
Yes. We build glazed extensions across Weston-super-Mare, including postcodes BS23. Every project starts with a free home visit.
Is VAT charged?
Yes, VAT at the standard 20% rate applies to extensions. Our guide prices include it.
