Covering Beckenham
We work in Beckenham (BR3) and the places around it, including Catford, Croydon and Blackheath.
Homes in London
London projects often mean working on period terraces with neighbours on both sides, tight access through the house and conservation area controls, so careful planning and party wall work matter as much as the build.
What does a side return extension involve?
Side returns are small in area but heavy in detail: party walls, a glazed roof, and steelwork to take out the original back wall. We design the roof for light and drainage, agree the party wall process early, and keep the work tidy because access is often through the house.
- Structural steel to remove the side wall
- Drainage and new gully positions
- Plastering and making good to the old house
How much should I budget for a side return extension?
What side return extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| 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 |
Planning and building rules in Beckenham
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. Deeper extensions, up to 6 m or 8 m, need prior approval from the council first.
What can affect a side return extension?
- Access is often through the house, so we plan deliveries and protect floors.
- Many terraces sit in conservation areas, where side extensions need planning permission.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- 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.
Your questions answered
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.
How long does a side return take?
About 10 to 14 weeks on site.
Do you work in Beckenham?
Yes. Beckenham is within our coverage for side return extensions, along with nearby Catford and Croydon.
Other towns nearby
- Side return extensions in Catford
- Side return extensions in Croydon
- Side return extensions in Blackheath
- Side return extensions in South Croydon
Learn more about side return extensions, or see every project we cover in Beckenham.

