Northumberland Park, Greater London
Single-storey rear extension in Northumberland Park
Single-storey rear extension in Northumberland Park: ground-floor space across the back of the house, usually for a kitchen, dining or family room. We measure the house, show you what the rules allow, price it in writing and build it.
Northumberland Park is covered from our Greater London round, including N9, N17 and N18. A single-storey rear extension in Northumberland Park is mostly built from the garden side, so the house stays usable for most of the job.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a single-storey rear extension cost in Northumberland Park?
Guide prices for a single-storey rear extension in Northumberland Park start from our London rate of £2,470–£4,030 per square metre, including VAT. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £29,500–£48,500 |
| 4 m wide × 5 m deep (20 m²) | £49,500–£80,500 |
| 4 m wide × 6 m deep (24 m²) | £59,500–£96,500 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a single-storey rear extension in Northumberland Park?
The planning route for a single-storey rear extension in Northumberland Park is set by England's householder rules and your council.
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Northumberland Park like to extend?
Period terraces in Northumberland Park sit alongside flats, and the difference matters: houses usually keep permitted development rights, while flats and maisonettes need planning permission for any rear extension.
How a single-storey rear extension in Northumberland Park comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Single-storey rear extensions near Northumberland Park
Close by, we work in Tottenham, about 0.4 miles away, and Tottenham Hale, about 0.7 miles away.
- Single-storey rear extension in Tottenham
- Single-storey rear extension in Tottenham Hale
- Single-storey rear extension in Edmonton
- Single-storey rear extension in Walthamstow
- Single-storey rear extension in Southgate
Other work in Northumberland Park:
FAQ
Single-storey rear extension questions in Northumberland Park
Can you match the brick or stone on my Northumberland Park house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
Is the site visit in Northumberland Park free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Do I need a structural engineer?
Yes for the beam over the new opening and usually for the foundations. Their calculations go to building control with the drawings.
How much does a single-storey rear extension cost in Northumberland Park?
As a guide, £2,470–£4,030 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £29,500–£48,500 at that rate. Your written price follows the survey.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.
What postcode areas do you cover around Northumberland Park?
Including N9, N17 and N18, and the surrounding Greater London area.