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 the West Midlands?
In the West Midlands, a glazed extension typically costs £2,700–£4,050 per m² of floor area, including VAT at 20% (standard rate). For a typical 18 m² project that is roughly £48,500–£73,000. Building costs in the West Midlands are close to the UK average, so the figures for the West Midlands are close to our national guide. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (13 m²) | £35,000–£52,500 |
| Typical project (18 m²) | £48,500–£73,000 |
| Larger project (25 m²) | £67,500–£101,000 |
| Rate per m² | £2,700–£4,050 |
Your quote will depend mainly on:
- Access for large glass panels
- Overheating and energy design
- Lighting and finishes
- Cladding material
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a glazed extension in the West Midlands?
The approval route for the West Midlands 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.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
What we take care of:
- Building control sign-off
- Large-format sliding doors and fixed glazing
- Energy and overheating calculations where needed
- Cladding or render finish
- Contemporary design and planning drawings
- Foundations, walls and insulated roof
How long does it take?
Build time is typically 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 the West Midlands
Across the West Midlands, inter-war and post-war semis make up much of the housing, giving good scope for two-storey side extensions and hip-to-gable lofts.
Towns we cover in the West Midlands include Birmingham, Coventry, Wolverhampton, Dudley, Walsall and Solihull.
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 in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about glazed extensions in the West Midlands
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.
Is VAT charged?
Yes, VAT at the standard 20% rate applies to extensions. Our guide prices include it.
How much does a glazed extension cost in the West Midlands?
In the West Midlands, a glazed extension typically costs £2,700–£4,050 per m² of floor area, including VAT at 20% (standard rate). A typical 18 m² project comes to roughly £48,500–£73,000. Your fixed price depends on the survey and drawings.
Do you build glazed extensions in the West Midlands?
Yes. We build glazed extensions across the West Midlands, including postcodes B1, B10, B11, B12 and B13. Every project starts with a free home visit.
Does it need planning permission?
The same rules as other extensions apply, but contemporary designs in conservation areas are assessed carefully. We discuss the design approach with you before applying.
