Thornbury, Bristol and South Gloucestershire
Bungalow rear extension in Thornbury
Bungalow rear extension in Thornbury: single-storey rear extensions that keep everything on one level. We measure the house, show you what the rules allow, price it in writing and build it.
Thornbury is covered from our Bristol and South Gloucestershire round, including BS35. For Thornbury bungalows we design the roof first, because the low eaves decide the height of the new room.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a bungalow rear extension cost in Thornbury?
A bungalow rear extension in Thornbury is priced at £1,920–£3,120 per square metre including VAT as a guide, before kitchen fit-out and fees. South West prices run slightly above our West Midlands baseline; natural stone to match the house is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £23,000–£37,500 |
| 4 m wide × 6 m deep (24 m²) | £46,000–£75,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a bungalow rear extension in Thornbury?
The planning route for a bungalow rear extension in Thornbury is set by England's householder rules and your council.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Thornbury like to extend?
Thornbury has Victorian terraces nearer the centre and post-war semis on the edges. Sloping gardens are frequent, which affects floor levels and steps down to the patio.
How a bungalow rear extension in Thornbury comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Bungalow rear extensions near Thornbury
Close by, we work in Stoke Gifford, about 6.4 miles away, and Yate, about 6.4 miles away.
- Bungalow rear extension in Stoke Gifford
- Bungalow rear extension in Yate
- Bungalow rear extension in Chepstow
- Bungalow rear extension in Mangotsfield
- Bungalow rear extension in Dursley
Other work in Thornbury:
FAQ
Bungalow rear extension questions in Thornbury
How much does a bungalow rear extension cost in Thornbury?
As a guide, £1,920–£3,120 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £23,000–£37,500 at that rate. Your written price follows the survey.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Can I extend the loft as well?
Sometimes, but that is a different project; a rear extension keeps everything on one level.
What postcode areas do you cover around Thornbury?
Including BS35, and the surrounding Bristol and South Gloucestershire area.
Is the site visit in Thornbury free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.