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 Bangor, Gwynedd?
In Bangor, a glazed extension typically costs £2,600–£3,850 per m² of floor area, including VAT at 20% (standard rate). For a typical 18 m² project that is roughly £47,000–£69,500. Building costs in Wales run about 8% below the UK average, and the figures for Bangor are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (13 m²) | £34,000–£50,000 |
| Typical project (18 m²) | £47,000–£69,500 |
| Larger project (25 m²) | £65,000–£96,000 |
| Rate per m² | £2,600–£3,850 |
The main things that change the cost:
- Cladding material
- Overheating and energy design
- Glazing size, specification and lead time
- Access for large glass panels
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 Bangor, Gwynedd?
Approvals for a glazed extension in Bangor follow the rules for Wales. In Wales a single-storey rear extension is often permitted development: up to 4 metres beyond the rear wall and up to 4 metres high, with eaves no higher than 3 metres within 2 metres of a boundary and no more than half the land around the original house covered. Wales has no larger home extension prior approval route, so deeper extensions need a planning application, as do extensions to flats, listed buildings and houses whose rights have been removed.
Building regulations in Wales are set by the Welsh Government. Approval comes from the council’s building control service or a registered building control approver, with inspections during the work and a completion certificate at the end.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
What we take care of:
- Cladding or render finish
- Energy and overheating calculations where needed
- Building control sign-off
- Structural design for steel frames and glass supports
- Foundations, walls and insulated roof
- Large-format sliding doors and fixed glazing
How long does it take?
The build itself usually takes 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 Bangor, Gwynedd
Wales has many terraced valley streets, stone cottages and post-war estates, so extension designs are shaped by slopes, materials and local character.
If your home is in Bangor or close by in Caernarfon, Llandudno and Colwyn Bay, a free home visit is the first step.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about glazed extensions in Bangor, Gwynedd
Do I need planning permission for a glazed extension in Bangor?
In Wales a single-storey rear extension is often permitted development: up to 4 metres beyond the rear wall and up to 4 metres high, with eaves no higher than 3 metres within 2 metres of a boundary and no more than half the land around the original house covered. Wales has no larger home extension prior approval route, so deeper extensions need a planning application, as do extensions to flats, listed buildings and houses whose rights have been removed.
Is VAT charged?
Yes, VAT at the standard 20% rate applies to extensions. Our guide prices include it.
Will a glass extension be too hot in summer?
It can be if poorly designed. Solar-control glass, roof overhangs and opening vents reduce overheating, and building regulations may require calculations to show the design works.
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 Bangor?
In Bangor, a glazed extension typically costs £2,600–£3,850 per m² of floor area, including VAT at 20% (standard rate). A typical 18 m² project comes to roughly £47,000–£69,500. Your fixed price depends on the survey and drawings.
Who approves a glazed extension in Bangor?
Planning matters in Bangor go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.