Northolt wraparound extensions, designed and built
A wraparound extension in Northolt starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in NortholtFrom £46,500 inc VAT
- PlanningUsually a householder application
- Build time14–20 weeks on site
- Postcode districtsHA2, UB5, UB6
What is included
- Structural design for the corner and openings
- Survey, design and 3D layout options
- Householder planning application
- Roof with glazing along the side return
- Foundations, drainage and any manhole relocation
What should I budget for a wraparound extension in Northolt?
Prices below are for Northolt, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Northolt: £2,600 to £4,810 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Compact L-shape 18 m² | £46,500 – £56,500 | £53,500 – £68,000 | £67,500 – £87,000 |
| Medium L-shape 25 m² | £65,000 – £78,000 | £74,500 – £94,500 | £94,000 – £120,500 |
| Large L-shape 32 m² | £83,000 – £100,000 | £95,500 – £121,000 | £120,500 – £154,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Extensions in and around Northolt
Across HA2, UB5, UB6, we can visit, measure and advise. Neighbouring towns we cover include Greenford (1 mile), South Ruislip (2 miles), Harrow (3 miles), Southall (3 miles).
London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
Do I need planning permission in Northolt?
In England a wraparound extension is assessed as both a side and a rear extension, and the combination usually falls outside permitted development, so most need a householder planning application (£548 from 1 April 2026).
The planning position for a specific Northolt address depends on its history and any designations, which is why we check it at the first visit.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
What happens next
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions people ask about wraparound extensions
Will my neighbours in Northolt be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Northolt, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in Northolt?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How much does a wraparound extension cost?
Our guide range is about £2,600 to £4,810 per m² including VAT. A 25 m² standard-spec wraparound typically lands around £74,500 to £94,500 in Northolt before design and council fees.
Do wraparound extensions need planning permission?
Usually, yes. In England the side element counts as a side extension and the rear element as a rear extension, and the combination normally falls outside permitted development. A householder application costs £548 in England from 1 April 2026.
Book a free site visit in Northolt
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.