What is a single-storey extension?
A single-storey extension is a ground-floor addition, usually at the rear of a house, that enlarges a kitchen, living or dining space. Most are built with cavity walls on concrete foundations and finished with a flat roof and roof lantern or a pitched tiled roof.
How much does a single-storey extension cost in Burnham-on-Sea?
In Burnham-on-Sea, a single-storey extension typically costs £2,000–£2,950 per m² of floor area, including VAT at 20% (standard rate). For a typical 20 m² project that is roughly £40,000–£59,000. Prices in the South West sit near the national average for this kind of work, and the range for Burnham-on-Sea reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (14 m²) | £28,000–£41,500 |
| Typical project (20 m²) | £40,000–£59,000 |
| Larger project (28 m²) | £56,000–£82,500 |
| Rate per m² | £2,000–£2,950 |
What moves the price most:
- Glazing: sliding and bifold doors cost more than French doors
- Roof type and the size of any lantern or roof windows
- Ground conditions and foundation depth
- Floor area and the length of new wall
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a single-storey extension in Burnham-on-Sea?
Whether you need planning permission depends on your house and its location 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.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served 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
On a typical single-storey extension we handle:
- Building control inspections and completion certificate
- First and second fix electrics, heating and plastering
- Foundations, drainage and any build-over agreement
- Knock-through to the existing house with steel beams
- Doors, windows and roof glazing installed
- Cavity walls, insulation and roof to current building regulations
How long does it take?
The build itself usually takes 10 to 14 weeks on site for a typical rear extension, after approvals. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Burnham-on-Sea
In parts of the South West, protected landscapes and conservation areas shape what can be built, so materials and roof forms are chosen carefully.
Our Burnham-on-Sea coverage includes postcode districts TA8, and we also work in nearby places such as Weston-super-Mare, Bridgwater and Clevedon.
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
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 single-storey extensions in Burnham-on-Sea
How much does a single-storey extension cost in Burnham-on-Sea?
In Burnham-on-Sea, a single-storey extension typically costs £2,000–£2,950 per m² of floor area, including VAT at 20% (standard rate). A typical 20 m² project comes to roughly £40,000–£59,000. Your fixed price depends on the survey and drawings.
Is VAT charged on an extension?
Yes. Building work on an existing home is standard-rated, so VAT at 20% applies. Our guide prices include it.
Do I need a party wall agreement?
If you are in England or Wales and the work involves a shared wall, building on the boundary or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We advise on this at the design stage.
How long does a single-storey extension take in Burnham-on-Sea?
Typically 10 to 14 weeks on site for a typical rear extension, after approvals. Design and approvals beforehand usually take 6 to 12 weeks.
Do I need planning permission for a single-storey extension?
Not always. Many small rear extensions are permitted development, within limits on depth, height and how much of the garden is covered. The limits depend on which nation you live in and on protected areas such as conservation areas, and flats or houses whose rights have been removed need an application. We check this at the survey and can apply to the council for formal confirmation.