Northumberland
Larger home extension prior approval (England) in Northumberland
Up to 6 m (attached) or 8 m (detached) deep, after neighbour consultation. Rear extensions in Northumberland: we cover 10 towns including Blyth, Cramlington and Ashington, with design, approvals and the build under one contract.

Terraces and semis are typical around Northumberland. On terraces a single-storey rear extension across the back yard is usually the practical choice; semis often have room for more.
How much does a prior approval rear extension cost in Northumberland?
Guide prices for a prior approval rear extension in Northumberland 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 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission in Northumberland?
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.
Where in Northumberland do we work?
FAQ
Questions people ask
How deep can I go with prior approval?
6 metres on attached houses and 8 metres on detached houses, single-storey only, up to 4 metres high.
Can my neighbours stop it?
They can object; the council then judges the effect on their amenity. Many schemes are approved after objections.
What happens after 42 days?
If the council has not decided, you can proceed. We still recommend waiting for written confirmation where possible.
Do you cover all of Northumberland?
We cover 10 towns and districts in Northumberland, including Blyth, Cramlington and Ashington.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.