Covering County Durham
Our double-storey extensions service in County Durham covers Darlington, Hartlepool, Stockton-on-Tees and Durham and more.
Homes in the North East
In the North East, terraces, semis and bungalows all offer room to extend, with stone-built villages and conservation areas in parts of County Durham and Northumberland.
What does a double-storey extension involve?
A double-storey extension adds new rooms on both the ground and first floor in one build, typically a larger kitchen or living space downstairs and an extra bedroom or bathroom above. Because the roof and foundations are shared, the cost per square metre is usually lower than a single-storey extension.
- Measured survey, design and planning drawings
- Windows, insulation, plastering, electrics and plumbing
- Joining the new first floor to the existing landing
How much should I budget for a double-storey extension?
Guide prices for double-storey extensions, including VAT where it applies. Your fixed price is confirmed in writing after the survey.
| Double-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,400 to £2,900 per m² |
| Good specification | £2,900 to £3,400 per m² |
| High specification | £3,400 to £3,850 per m² |
What approvals does a double-storey extension need in England?
Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.
Two-storey rear extensions can sometimes be permitted development in England (no more than 3 m deep, at least 7 m from the rear boundary, roof pitch to match), but most two-storey and all two-storey side extensions need householder planning permission.
What can affect a double-storey extension?
- Neighbours’ light is assessed using the 45-degree guide many councils use.
- The first-floor link can mean moving a bathroom or reshaping the landing.
What happens after I enquire?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
What people ask before starting
Is a two-storey extension better value than a single-storey one?
Per square metre, usually yes, because the foundations and roof serve two floors of space.
How long does a two-storey extension take?
Around 14 to 24 weeks on site, plus the planning period before that.
Who deals with the council for a project in County Durham?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Other towns nearby
- Double-storey extensions in Darlington
- Double-storey extensions in Hartlepool
- Double-storey extensions in Stockton-on-Tees
- Double-storey extensions in Durham
- Double-storey extensions in Chester-le-Street
- Double-storey extensions in Billingham
- Double-storey extensions in Stanley
- Double-storey extensions in Consett
- Double-storey extensions in Newton Aycliffe
- Double-storey extensions in Bishop Auckland
- Double-storey extensions in Seaham
Learn more about double-storey extensions, or see every project we cover in County Durham.