Northallerton, North Yorkshire
Single-storey rear extension in Northallerton
Single-storey rear extension in Northallerton: 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.
Northallerton and its postcode districts DL6 and DL7 are part of our North Yorkshire coverage. A single-storey rear extension in Northallerton 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 Northallerton?
Guide prices for a single-storey rear extension in Northallerton start from our Yorkshire and the Humber rate of £1,770–£2,880 per square metre, including VAT. Yorkshire prices sit below our West Midlands baseline; matching natural stone is the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,000–£34,500 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£57,500 |
| 4 m wide × 6 m deep (24 m²) | £42,500–£69,000 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a single-storey rear extension in Northallerton?
The planning route for a single-storey rear extension in Northallerton is set by England's householder rules and your council.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Northallerton like to extend?
Northallerton has through terraces and some back-to-backs as well as later semis; back-to-backs have little or no rear space, so we look at side or loft options there.
How a single-storey rear extension in Northallerton comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Single-storey rear extensions near Northallerton
Neighbouring places we cover include Yarm (11.8 miles) and Catterick Garrison (12.0 miles).
- Single-storey rear extension in Yarm
- Single-storey rear extension in Catterick Garrison
- Single-storey rear extension in Ingleby Barwick
- Single-storey rear extension in Darlington
- Single-storey rear extension in Thornaby-on-Tees
Other work in Northallerton:
FAQ
Single-storey rear extension questions in Northallerton
How long does a rear extension take to build in Northallerton?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.
Is a flat roof or a pitched roof better?
A warm flat roof keeps the extension low under first-floor windows and suits a roof lantern; a pitched or lean-to roof gives a vaulted ceiling. Both last for decades when built properly.
What postcode areas do you cover around Northallerton?
Including DL6 and DL7, and the surrounding North Yorkshire area.
How much does a single-storey rear extension cost in Northallerton?
As a guide, £1,770–£2,880 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £21,000–£34,500 at that rate. Your written price follows the survey.
Is the site visit in Northallerton free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.