What is a side return extension?
A side return extension fills the narrow passage that runs alongside the back addition of many Victorian and Edwardian terraced houses. It widens a galley kitchen into a proper kitchen-diner, usually with a sloping glazed roof to keep the room bright.
How much does a side return extension cost in Wiltshire?
In Wiltshire, a side return extension typically costs £2,350–£3,350 per m² of floor area, including VAT at 20% (standard rate). For a typical 12 m² project that is roughly £28,000–£40,000. Prices in the South West sit near the national average for this kind of work, and the range for Wiltshire reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (8 m²) | £19,000–£27,000 |
| Typical project (12 m²) | £28,000–£40,000 |
| Larger project (17 m²) | £40,000–£57,000 |
| Rate per m² | £2,350–£3,350 |
What moves the price most:
- Glazed roof specification
- Length of the side return
- Steel beams and propping of the back addition
- Access through the house for materials
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 side return extension in Wiltshire?
The approval route for Wiltshire is set by planning law in England. In England a side return infill is treated as a side extension. It may be permitted development if it is single-storey, no more than 4 metres high and no wider than half the original house, but not in a conservation area. Because side returns sit on the boundary, party wall notices are almost always needed.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
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:
- Foundations and drainage, including any build-over agreement
- Floor levelling, heating and electrics
- Drawings and planning or permitted development check
- Steel beams to remove the side wall
- Party wall advice and notices
- Building control sign-off
How long does it take?
Build time is typically 10 to 14 weeks on site. Before that, surveys, drawings and approvals usually take 3 to 4 months, longer if the council asks for changes.
Building in Wiltshire
In parts of the South West, protected landscapes and conservation areas shape what can be built, so materials and roof forms are chosen carefully.
Towns we cover in Wiltshire include Swindon, Salisbury, Trowbridge, Chippenham and Melksham.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 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 side return extensions in Wiltshire
How much space does a side return add?
Typically 1.5 to 2.5 metres of width along the back addition. It often turns a narrow galley kitchen into a family kitchen-diner.
How much does a side return extension cost in Wiltshire?
In Wiltshire, a side return extension typically costs £2,350–£3,350 per m² of floor area, including VAT at 20% (standard rate). A typical 12 m² project comes to roughly £28,000–£40,000. Your fixed price depends on the survey and drawings.
Can I stay in the house?
Usually, though the kitchen will be out of action for several weeks. We plan a temporary kitchen area where possible.
Who approves a side return extension in Wiltshire?
Planning matters in Wiltshire go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
How do you get materials in?
Mid-terrace houses often have no rear access, so materials come through the house. We protect floors and plan deliveries carefully.