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 Formby?
In Formby, a glazed extension typically costs £2,650–£3,950 per m² of floor area, including VAT at 20% (standard rate). For a typical 18 m² project that is roughly £47,500–£71,000. That range is adjusted for the North West, where domestic building work typically costs around 6% below the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (13 m²) | £34,500–£51,500 |
| Typical project (18 m²) | £47,500–£71,000 |
| Larger project (25 m²) | £66,000–£99,000 |
| Rate per m² | £2,650–£3,950 |
The main things that change the cost:
- Steel framing
- Lighting and finishes
- Cladding material
- Overheating and energy design
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 Formby?
Here is how the rules work for a glazed extension 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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
What we take care of:
- Cladding or render finish
- Foundations, walls and insulated roof
- Building control sign-off
- Electrics, heating and finishes
- Energy and overheating calculations where needed
- Structural design for steel frames and glass supports
How long does it take?
Expect 12 to 16 weeks on site; glazing lead times can be 6 to 10 weeks. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Formby
The North West has many brick terraces and inter-war semis, where kitchen extensions and dormer loft conversions add space without moving.
We work across Formby and neighbouring areas such as Maghull, Southport and Bootle. Postcodes we cover in Formby include L37.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about glazed extensions in Formby
Can large glass panels be lifted in?
Some need a crane or glass-lifting robot. We plan access during design.
How long does a glazed extension take in Formby?
Typically 12 to 16 weeks on site; glazing lead times can be 6 to 10 weeks. Design and approvals beforehand usually take 3 to 4 months.
Is VAT charged?
Yes, VAT at the standard 20% rate applies to extensions. Our guide prices include it.
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 Formby?
In Formby, a glazed extension typically costs £2,650–£3,950 per m² of floor area, including VAT at 20% (standard rate). A typical 18 m² project comes to roughly £47,500–£71,000. Your fixed price depends on the survey and drawings.