Side return extensions in Acton

Covering Acton

We work in Acton (W3) and the places around it, including Chiswick, Shepherd's Bush and Willesden.

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 goes into a side return extension?

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.

Party wall notices and surveyor liaison
Glazed or solid roof with rooflights
Underfloor heating ready screed if wanted

What is the guide price for a side return extension in Acton?

Indicative costs for side return extensions. London and the South East usually sit towards the top of each range.

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 Acton

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 should I think about before starting?

Most side returns touch a shared boundary, so the Party Wall etc. Act 1996 usually applies in England and Wales.
Many terraces sit in conservation areas, where side extensions need planning permission.

How does the project run?

Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

What people ask before starting

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.

Will I need a party wall agreement?

Most likely, because the new wall usually sits on or near the boundary. We serve the notices and work with your neighbour’s surveyor if one is appointed.

Do you work in Acton?

Yes. Acton is within our coverage for side return extensions, along with nearby Chiswick and Shepherd's Bush.

Also covering

Learn more about side return extensions, or see every project we cover in Acton.