Seaham, County Durham
Kitchen-diner rear extension in Seaham
Thinking about a kitchen-diner rear extension in Seaham? An open-plan kitchen, dining and family room that opens straight onto the garden. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Seaham is covered from our County Durham round, including SR7. A kitchen-diner is often the reason people in Seaham extend: the back kitchen in terraces and semis is rarely big enough for a table.
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 kitchen-diner rear extension cost in Seaham?
A kitchen-diner rear extension in Seaham 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 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a kitchen-diner rear extension in Seaham?
Here is how the rules in England apply to a kitchen-diner rear extension in Seaham.
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. 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 Seaham like to extend?
Terraces and semis are typical around Seaham. On terraces a single-storey rear extension across the back yard is usually the practical choice; semis often have room for more.
How a kitchen-diner rear extension in Seaham 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.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Kitchen-diner rear extensions near Seaham
Close by, we work in Ryhope, about 2.4 miles away, and Hetton-le-Hole, about 4.4 miles away.
- Kitchen-diner rear extension in Ryhope
- Kitchen-diner rear extension in Hetton-le-Hole
- Kitchen-diner rear extension in Houghton-le-Spring
- Kitchen-diner rear extension in Sunderland
- Kitchen-diner rear extension in Peterlee
Other work in Seaham:
FAQ
Kitchen-diner rear extension questions in Seaham
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Do I need planning permission for a rear extension in Seaham?
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.
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.
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.
Do you handle building control in Seaham?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
How much does a kitchen-diner rear extension cost in Seaham?
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.