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 Dumbarton?
In Dumbarton, 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 Dumbarton 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
- Glazing size, specification and lead time
- Overheating and energy design
- Lighting and finishes
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a glazed extension in Dumbarton?
Approvals for a glazed extension in Dumbarton follow the rules for 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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
From survey to sign-off, the job normally involves:
- Contemporary design and planning drawings
- Building control sign-off
- Structural design for steel frames and glass supports
- Cladding or render finish
- Foundations, walls and insulated roof
- Energy and overheating calculations where needed
How long does it take?
Allow 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 Dumbarton
In Scotland, bungalows and one-and-a-half-storey homes are common, so dormer conversions are a popular way to add bedrooms.
Our Dumbarton coverage includes postcode districts G82, and we also work in nearby places such as Erskine, Clydebank and Greenock.
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
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about glazed extensions in Dumbarton
Who approves a glazed extension in Dumbarton?
Planning matters in Dumbarton go to the council covering your address, and the work needs a building warrant. We prepare and submit the applications for you.
How much does a glazed extension cost in Dumbarton?
In Dumbarton, 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.
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.
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.
Do I need planning permission for a glazed extension in Dumbarton?
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.