Covering Dartford
Our coverage around Dartford (DA1) also includes Bexley (3 miles to the west) and Swanley.
Homes in the South East
Housing across the South East mixes inter-war semis, post-war estates and older cottages in villages and market towns, so rear and side extensions, hip-to-gable lofts and garage conversions all come up regularly.
What do you get with a double-storey extension?
Two-storey work has to sit comfortably with the house and the neighbours, so most of the design effort goes into the roofline, window positions and how the new first floor connects to the landing. We handle the planning application, the structural design and the building control process, then build, roof and finish both floors.
- Measured survey, design and planning drawings
- Foundations, steelwork, brick and block walls, roof
- Windows, insulation, plastering, electrics and plumbing
How much does a double-storey extension cost in Dartford?
What double-storey extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| 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 |
How is a double-storey extension approved in Dartford?
English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.
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. Expect around eight weeks for a decision once the application is validated.
What should I think about before starting?
- Side extensions close to a boundary are often set back or stepped down so they do not create a terraced effect.
- 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.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
What people ask before starting
How much does a two-storey extension cost?
Typically about £2,400 to £3,850 per square metre of new floor area including VAT. A 40 m² extension across two floors is often around £100,000 to £150,000 depending on specification.
How long does a two-storey extension take?
Around 14 to 24 weeks on site, plus the planning period before that.
Can you visit a house in Dartford to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Double-storey extensions in nearby towns
- Double-storey extensions in Bexley
- Double-storey extensions in Swanley
- Double-storey extensions in Welling
- Double-storey extensions in South Ockendon
Learn more about double-storey extensions, or see every project we cover in Dartford.