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 County Armagh?
In County Armagh, a glazed extension typically costs £2,400–£3,600 per m² of floor area, including VAT at 20% (standard rate). For a typical 18 m² project that is roughly £43,000–£65,000. Prices across Northern Ireland are typically 14% below the UK average for this kind of work, which is reflected in the range for County Armagh. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (13 m²) | £31,000–£47,000 |
| Typical project (18 m²) | £43,000–£65,000 |
| Larger project (25 m²) | £60,000–£90,000 |
| Rate per m² | £2,400–£3,600 |
The main things that change the cost:
- Access for large glass panels
- Steel framing
- Cladding material
- Overheating and energy design
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 County Armagh?
Whether you need planning permission depends on your house and its location in Northern Ireland. In Northern Ireland the Planning (General Permitted Development) Order (Northern Ireland) 2015 allows single-storey rear extensions of up to 3 metres on attached houses and 4 metres on detached houses, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary. Houses with removed rights need planning permission, listed buildings need consent, and in conservation areas extensions must stay single-storey and must not come forward of the front or side walls.
Northern Ireland has no Party Wall Act. Work on shared walls relies on agreement with the neighbour and common law, so we agree the arrangements in writing 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
What we take care of:
- Structural design for steel frames and glass supports
- Building control sign-off
- Cladding or render finish
- Foundations, walls and insulated roof
- Contemporary design and planning drawings
- Large-format sliding doors and fixed glazing
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 County Armagh
Across Northern Ireland, bungalows and chalet bungalows are common, so loft conversions and rear extensions are popular projects.
Towns we cover in County Armagh include Craigavon, Portadown and Armagh.
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
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 County Armagh
How long does a glazed extension take in County Armagh?
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.
Can large glass panels be lifted in?
Some need a crane or glass-lifting robot. We plan access during design.
Do I need planning permission for a glazed extension in County Armagh?
In Northern Ireland the Planning (General Permitted Development) Order (Northern Ireland) 2015 allows single-storey rear extensions of up to 3 metres on attached houses and 4 metres on detached houses, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary. Houses with removed rights need planning permission, listed buildings need consent, and in conservation areas extensions must stay single-storey and must not come forward of the front or side walls.
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 County Armagh?
In County Armagh, a glazed extension typically costs £2,400–£3,600 per m² of floor area, including VAT at 20% (standard rate). A typical 18 m² project comes to roughly £43,000–£65,000. Your fixed price depends on the survey and drawings.
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.
