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 Limavady?
In Limavady, a side return extension typically costs £2,000–£2,850 per m² of floor area, including VAT at 20% (standard rate). For a typical 12 m² project that is roughly £24,000–£34,000. We start from a UK-wide guide and adjust it for Northern Ireland, where labour and materials are typically about 14% below average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (8 m²) | £16,000–£23,000 |
| Typical project (12 m²) | £24,000–£34,000 |
| Larger project (17 m²) | £34,000–£48,500 |
| Rate per m² | £2,000–£2,850 |
The biggest cost drivers are:
- Agreements with neighbours on shared walls
- Glazed roof specification
- Length of the side return
- 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 Limavady?
Here is how the rules work for a side return extension in Northern Ireland. In Northern Ireland a single-storey side infill can be permitted development if it is no more than 4 metres high and no wider than half the original house; conservation areas need planning permission. Building control approval is needed before work starts.
In Northern Ireland building control approval comes from the council, usually through a full plans application or a building notice, with inspections during the work and a completion certificate at the end.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
The work we manage on a side return extension:
- Foundations and drainage, including any build-over agreement
- Glazed or solid roof with insulation
- Building control sign-off
- Drawings and planning or permitted development check
- Written agreement with neighbours on shared walls
- Written agreement with neighbours on shared walls
How long does it take?
Expect 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 Limavady
Northern Ireland has many detached and semi-detached homes on generous plots, which suits single-storey rear extensions and garage conversions.
Our Limavady coverage includes postcode districts BT49, and we also work in nearby places such as Coleraine, Derry and Magherafelt.
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
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about side return extensions in Limavady
Do I need planning permission for a side return extension in Limavady?
In Northern Ireland a single-storey side infill can be permitted development if it is no more than 4 metres high and no wider than half the original house; conservation areas need planning permission. Building control approval is needed before work starts.
Do you build side return extensions in Limavady?
Yes. We build side return extensions across Limavady, including postcodes BT49. Every project starts with a free home visit.
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.
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.
How much does a side return extension cost in Limavady?
In Limavady, a side return extension typically costs £2,000–£2,850 per m² of floor area, including VAT at 20% (standard rate). A typical 12 m² project comes to roughly £24,000–£34,000. Your fixed price depends on the survey and drawings.
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.
