Covering Barnet
Alongside Barnet, we also cover Potters Bar, Borehamwood (3 miles to the west) and Finchley.
Homes in London
Terraced houses dominate many London neighbourhoods, so most projects involve shared walls, narrow access and a party wall process. Conservation areas are widespread, and some boroughs have their own mansard and basement guidance.
What does a side return extension involve?
A side return extension builds over the narrow passage that runs beside the back of many Victorian and Edwardian terraced houses, widening the kitchen or dining room by a metre or two. It is usually combined with a glazed or part-glazed roof so the deeper room still gets daylight.
- Glazed or solid roof with rooflights
- Drainage and new gully positions
- Underfloor heating ready screed if wanted
How much does a side return extension cost in Barnet?
Typical ranges for side return extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Side return extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £3,350 to £3,700 per m² |
| Good specification | £3,700 to £4,150 per m² |
| High specification | £4,150 to £4,550 per m² |
Do you need permission for a side return extension in Barnet?
Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.
In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary.
What can affect a side return extension?
- Access is often through the house, so we plan deliveries and protect floors.
- Glazed roofs need careful detailing against the neighbour’s wall.
From first call to completion
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Questions about a side return extension in Barnet
How much does a side return extension cost?
Usually about £3,350 to £4,550 per square metre including VAT, which works out at around £35,000 to £55,000 for a typical side return before the kitchen.
Does a side return need planning permission?
In England it can be permitted development if it is single storey, no higher than 4 m and no wider than half the original house. Conservation areas are the main exception.
How do I get a price for side return extensions in Barnet?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Side return extensions in nearby towns
- Side return extensions in Potters Bar
- Side return extensions in Borehamwood
- Side return extensions in Finchley
- Side return extensions in Muswell Hill
Learn more about side return extensions, or see every project we cover in Barnet.