Double-storey extensions in Blyth
A double-storey extension in Blyth starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in BlythFrom £34,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsNE24
Local to Blyth
Postcode districts we cover around Blyth include NE24. We also work in nearby Bedlington (3 miles), Ashington (4 miles), Cramlington (4 miles), Morpeth (8 miles).
Whitley Bay, in Tyne and Wear, is roughly 7 miles from Blyth and also on our list. Across the North East, houses often have rear yards or modest gardens, so compact, well-lit single-storey extensions make the biggest difference.
What is included
- Foundations sized for two floors
- Householder planning application where needed
- Ground and first floor structure, roof tied into the existing roof
- Building regulations drawings and structural design
The roof is what makes a two-storey extension look right or wrong. We match the pitch and materials of the main house wherever possible and plan the upstairs layout around the existing landing so the new rooms feel original rather than bolted on.
Do I need planning permission in Blyth?
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
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).
Guide prices for Blyth
Labour and material costs vary across the UK, so for Blyth we use our North East England factor (×0.91). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Blyth: £1,410 to £2,730 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £34,500 – £41,500 | £39,000 – £51,500 | £50,000 – £66,000 |
| 4 m × 4 m, two floors 32 m² | £45,000 – £54,000 | £52,000 – £68,500 | £66,500 – £87,500 |
| 4 m × 6 m, two floors 48 m² | £67,500 – £81,000 | £78,500 – £103,000 | £100,000 – £131,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
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
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Double-storey extension questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Blyth, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in Blyth?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who do I contract with for a double-storey extension in Blyth?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Do I need a Party Wall Agreement?
If you are in England or Wales and the work involves a shared wall or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We tell you which notices are needed.
Is a two-storey extension cheaper per square metre?
Usually. Our guide range is about £1,410 to £2,730 per m² of new floor area including VAT, compared with £1,590 to £3,090 per m² for single-storey work, because the foundations and roof are shared across two floors.
Book a free site visit in Blyth
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.