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 Bury St Edmunds?
In Bury St Edmunds, a side return extension typically costs £2,450–£3,500 per m² of floor area, including VAT at 20% (standard rate). For a typical 12 m² project that is roughly £29,500–£42,000. We start from a UK-wide guide and adjust it for the East of England, where labour and materials are typically about 6% above average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (8 m²) | £19,500–£28,000 |
| Typical project (12 m²) | £29,500–£42,000 |
| Larger project (17 m²) | £41,500–£59,500 |
| Rate per m² | £2,450–£3,500 |
The main things that change the cost:
- Moving drains and soil stacks
- Party wall surveyor fees
- Length of the side return
- Access through the house for materials
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a side return extension in Bury St Edmunds?
Whether you need planning permission depends on your house and its location 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.
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
What we take care of:
- Foundations and drainage, including any build-over agreement
- Survey of party walls, drains and the existing back addition
- Building control sign-off
- Drawings and planning or permitted development check
- Glazed or solid roof with insulation
- Steel beams to remove the side wall
How long does it take?
Allow 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 Bury St Edmunds
Many towns in the East of England have estates built since the 1970s, where garage conversions and rear extensions are popular.
Projects in Bury St Edmunds (IP32 and IP33) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 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 Bury St Edmunds
Do you build side return extensions in Bury St Edmunds?
Yes. We build side return extensions across Bury St Edmunds, including postcodes IP32 and IP33. Every project starts with a free home visit.
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.
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.
Is a glass roof too hot or cold?
Modern solar-control double or triple glazing reduces glare and heat loss. Building regulations also limit how much glazing you can have unless the design shows it performs well enough.
How much does a side return extension cost in Bury St Edmunds?
In Bury St Edmunds, a side return extension typically costs £2,450–£3,500 per m² of floor area, including VAT at 20% (standard rate). A typical 12 m² project comes to roughly £29,500–£42,000. Your fixed price depends on the survey and drawings.
