Northumberland
Kitchen-diner rear extensions in Northumberland
An open-plan kitchen, dining and family room that opens straight onto the garden. We design and build rear extensions across Northumberland, from Blyth and Cramlington to Ashington, covering single-storey kitchen extensions, two-storey additions, side returns and wraparounds.

We usually keep the working kitchen where the old one was and put the dining table in the new space by the doors, which suits most Blyth homes. 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 kitchen-diner rear extension cost in Northumberland?
A kitchen-diner rear extension in Northumberland is priced at £1,710–£2,790 per square metre including VAT as a guide, before kitchen fit-out and fees. 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 in Northumberland?
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.
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
Should the sink face the garden?
If the plan allows, an island sink or hob facing the glass is a common choice. It needs a floor-level drain run, which is easy to lay in a new slab.
Can I have underfloor heating?
Yes. Wet underfloor heating in the new screed is the usual choice, often with the old room's radiators kept or replaced.
Where does the cooker extraction go?
Through the new wall or roof, ducted to outside. Recirculating hoods are possible but less effective.
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.