Ashington, Northumberland
Semi-detached rear extension in Ashington
For homes in Ashington, a semi-detached rear extension is often the simplest way to gain space without moving. Single or two-storey extensions for semi-detached houses, with side access and one party wall. We take it from survey to completion certificate.
Ashington sits in Northumberland, with postcode districts including NE62, NE63 and NE64. In Ashington we measure the attached neighbour's extension at the survey, because it often sets the sensible depth for yours.
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 semi-detached rear extension cost in Ashington?
Guide prices for a semi-detached rear extension in Ashington start from our North East England rate of £1,710–£2,790 per square metre, including VAT. North East prices are among the lowest in our range; former mining ground is the main foundation variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £20,500–£33,500 |
| 4 m wide × 5 m deep (20 m²) | £34,000–£56,000 |
| 4 m wide × 6 m deep (24 m²) | £41,000–£67,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a semi-detached rear extension in Ashington?
Here is how the rules in England apply to a semi-detached rear extension in Ashington.
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.
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
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 Ashington like to extend?
Terraces and semis are typical around Ashington. On terraces a single-storey rear extension across the back yard is usually the practical choice; semis often have room for more.
How a semi-detached rear extension in Ashington 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.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
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.
Semi-detached rear extensions near Ashington
Neighbouring places we cover include Bedlington (3.4 miles) and Blyth (4.1 miles).
- Semi-detached rear extension in Bedlington
- Semi-detached rear extension in Blyth
- Semi-detached rear extension in Morpeth
- Semi-detached rear extension in Cramlington
- Semi-detached rear extension in Whitley Bay
Other work in Ashington:
FAQ
Semi-detached rear extension questions in Ashington
How much does a semi-detached rear extension cost in Ashington?
As a guide, £1,710–£2,790 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £20,500–£33,500 at that rate. Your written price follows the survey.
Can you match the brick or stone on my Ashington house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
What if my neighbour has already extended?
That can make a matching depth easier to justify. We measure theirs at the survey.
Do I need planning permission for a rear extension in Ashington?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
What postcode areas do you cover around Ashington?
Including NE62, NE63 and NE64, and the surrounding Northumberland area.
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.