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 Brecon?
In Brecon, a side return extension typically costs £2,100–£3,050 per m² of floor area, including VAT at 20% (standard rate). For a typical 12 m² project that is roughly £25,000–£36,500. Building costs in Wales run about 8% below the UK average, and the figures for Brecon are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (8 m²) | £17,000–£24,500 |
| Typical project (12 m²) | £25,000–£36,500 |
| Larger project (17 m²) | £35,500–£52,000 |
| Rate per m² | £2,100–£3,050 |
What moves the price most:
- Glazed roof specification
- Party wall surveyor fees
- Steel beams and propping of the back addition
- Length of the side return
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a side return extension in Brecon?
Approvals for a side return extension in Brecon follow the rules for Wales. In Wales a side return infill is treated as a single-storey side extension: it can be permitted development within the 4 metre height and 50% width limits, but many terraced streets are in conservation areas or have removed rights. Party wall notices are usually needed.
The Party Wall etc. Act 1996 applies in Wales, so notices must be served before work on a shared wall, on the boundary, or excavation close to a neighbour’s foundations.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most side return extensions:
- Drawings and planning or permitted development check
- Steel beams to remove the side wall
- Floor levelling, heating and electrics
- Glazed or solid roof with insulation
- Party wall advice and notices
- Foundations and drainage, including any build-over agreement
How long does it take?
Build time is typically 10 to 14 weeks on site. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Brecon
Terraced houses in Welsh towns often have narrow plots, which suits rear and side return extensions and rear dormers.
We work across Brecon and neighbouring areas such as Merthyr Tydfil, Ebbw Vale and Aberdare. Postcodes we cover in Brecon include LD3.
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
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about side return extensions in Brecon
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.
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.
Do I need planning permission for a side return extension in Brecon?
In Wales a side return infill is treated as a single-storey side extension: it can be permitted development within the 4 metre height and 50% width limits, but many terraced streets are in conservation areas or have removed rights. Party wall notices are usually needed.
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.
Do you build side return extensions in Brecon?
Yes. We build side return extensions across Brecon, including postcodes LD3. Every project starts with a free home visit.
How much does a side return extension cost in Brecon?
In Brecon, a side return extension typically costs £2,100–£3,050 per m² of floor area, including VAT at 20% (standard rate). A typical 12 m² project comes to roughly £25,000–£36,500. Your fixed price depends on the survey and drawings.