Wraparound extensions in Isleworth

Covering Isleworth

We work in Isleworth (TW7) and the places around it, including Hounslow, Heston and Richmond.

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 wraparound extension?

A wraparound extension combines a side return and a rear extension into one L-shaped build, giving the biggest possible ground-floor space on terraced and semi-detached houses. It usually creates a large open-plan kitchen, dining and living area across the back of the house.

Design, planning drawings and structural calculations
Party wall process with both neighbours if needed
Glazing, insulation, plastering and electrics

How much should I budget for a wraparound extension?

Use these ranges to budget for wraparound extensions; the survey turns them into a fixed price for the agreed specification.

Wraparound extensions	Guide price incl. VAT
Standard specification	£3,400 to £3,800 per m²
Good specification	£3,800 to £4,250 per m²
High specification	£4,250 to £4,700 per m²

Do you need permission for a wraparound extension in Isleworth?

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 wraparound extension is treated as one extension, and because it covers both the side and the rear it does not normally fit within permitted development. Most need householder planning permission, which usually takes around eight weeks once validated.

What should I think about before starting?

The corner steel connection is the critical detail and is designed by a structural engineer.
Roof water from an L-shape needs careful falls and outlets.

How does the project run?

Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
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.

Your questions answered

Can we keep part of the kitchen working?

Often, by sequencing the work so the old back wall comes out last. We agree a plan with you before starting.

Glazed roof or solid roof?

A mix usually works best: solid roof with rooflights over the kitchen and a glazed section over the dining area.

Can you visit a house in Isleworth to quote?

Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.

Wraparound extensions in nearby towns

Learn more about wraparound extensions, or see every project we cover in Isleworth.