Extending your home in Seaham
Looking to extend your home in Seaham? Start here: extension types, guide prices for Seaham, the planning rules that apply and how a project runs.
- Postcode districtsSR7
- Price regionNorth East England (×0.91)
- Planning rulesEngland
- Site visitFree, no obligation
Do extensions in Seaham need planning permission?
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In England a single-storey side return infill is often permitted development if it stays within the height limits and is no wider than half the width of the original house. Conservation areas, listed buildings and flats always need an application, and the boundary wall usually brings in the Party Wall Act.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Covering Seaham and nearby
We cover Seaham and the postcode districts SR7. We also work in nearby Peterlee (5 miles), Chester-le-Street (9 miles), Durham (10 miles), Hartlepool (12 miles), Stanley (14 miles). For homes towards Tyne and Wear, Houghton-le-Spring is around 5 miles away.
Seaham extension prices at a glance
Use these Seaham guide prices to sense-check a budget; the guide-price tool narrows them to your own size, and the site visit turns them into a written figure.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Conservatory replacement extensions | 14 m² | £27,000 – £35,500 |
| Side return extensions | 11 m² | £24,000 – £30,500 |
| Single-storey rear extensions | 20 m² | £37,000 – £47,500 |
| Extensions over a garage | 12 m² | £22,500 – £29,500 |
| Wraparound extensions | 25 m² | £52,000 – £66,000 |
| Double-storey extensions | 32 m² | £52,000 – £68,500 |
| Kitchen extensions | 20 m² | £38,000 – £48,500 |
Which extension suits a Seaham home?
Across the North East, houses often have rear yards or modest gardens, so compact, well-lit single-storey extensions make the biggest difference.
For many houses here, single-storey rear extensions, double-storey extensions or kitchen extensions gives the most useful space for the budget.
All extension types we build in Seaham
- Kitchen extensions · from £24,500
- Building regulations for extensions · from £800
- Double-storey extensions · from £34,500
- Bedroom extensions · from £23,500
- Wraparound extensions · from £32,500
- Bungalow extensions · from £23,500
- Timber frame extensions · from £19,000
- Side extensions · from £20,000
- Single-storey rear extensions · from £19,000
- Planning permission for extensions · from £300
- Annexe extensions · from £50,000
- Orangery extensions · from £27,000
- Flat roof extensions · from £19,000
- Conservatory replacement extensions · from £18,000
- Utility and boot room extensions · from £12,500
- Porch extensions · from £3,600
- Side return extensions · from £16,000
- Glass box extensions · from £27,000
- Extensions over a garage · from £21,500
- Pitched roof extensions · from £20,000
- Home office extensions · from £14,500
- Extension plans and drawings · from £1,050
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions about extensions in Seaham
How much does an extension cost in Seaham?
Using our North East England factor (×0.91), a standard-spec single-storey extension of 20 m² is a guide £37,000 to £47,500 including VAT, and a 32 m² two-storey extension £52,000 to £68,500. Your written price follows the survey.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Seaham, and the guide-price tool gives a range for your own size and finish in about a minute.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Do you cover all of Seaham?
Yes, including the surrounding parts of County Durham. Site visits are free and there is no obligation.
Book a free site visit in Seaham
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.