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 Kelso?
In Kelso, 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 Scotland are close to the UK average, so the figures for Kelso 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 |
The main things that change the cost:
- Lighting and finishes
- Cladding material
- Overheating and energy design
- 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 Kelso?
Whether you need planning permission depends on your house and its location in Scotland. In Scotland a single-storey extension is often permitted development (Class 1A): where any part is within 1 metre of a boundary, it can project up to 3 metres from the rear wall of a terraced house or 4 metres on other houses, with eaves no higher than 3 metres, an overall height of 4 metres and no more than half the front or rear garden covered. The rights do not apply in conservation areas or to flats, and a building warrant will usually still be needed before work starts.
Scotland has no Party Wall Act. Work on shared walls is governed by your title deeds, the Tenements (Scotland) Act 2004 for flats, and common law, so we agree arrangements with neighbours in writing before work starts.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most glazed extensions:
- Large-format sliding doors and fixed glazing
- Energy and overheating calculations where needed
- Foundations, walls and insulated roof
- Contemporary design and planning drawings
- Structural design for steel frames and glass supports
- Building control sign-off
How long does it take?
Build time is typically 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 Kelso
In Scotland, bungalows and one-and-a-half-storey homes are common, so dormer conversions are a popular way to add bedrooms.
Kelso sits in the Scottish Borders, about 15 miles east of Galashiels. We cover the whole of Kelso, including postcodes TD5.
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 pricing
Design options, then a fixed quote based on the chosen drawings and 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 Kelso
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 Kelso?
In Scotland a single-storey extension is often permitted development (Class 1A): where any part is within 1 metre of a boundary, it can project up to 3 metres from the rear wall of a terraced house or 4 metres on other houses, with eaves no higher than 3 metres, an overall height of 4 metres and no more than half the front or rear garden covered. The rights do not apply in conservation areas or to flats, and a building warrant will usually still be needed before work starts.
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.
How much does a glazed extension cost in Kelso?
In Kelso, 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 Kelso?
Yes. We build glazed extensions across Kelso, including postcodes TD5. Every project starts with a free home visit.
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.
