Covering Dagenham
Dagenham sits 13 miles east of London, with Becontree 2 miles to the west and Romford 2 miles to the north-east.
Homes in London
Much of London’s housing is Victorian and Edwardian terraces, which is why side return extensions, rear dormers and mansards are so common. Many streets are in conservation areas, and several boroughs use Article 4 directions that remove some permitted development rights.
What does a double-storey extension involve?
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
What will a double-storey extension cost?
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 Dagenham?
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.
What can change the price or programme?
- 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?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- 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.
Your questions answered
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.
Does a two-storey extension need planning permission?
Usually yes. In England some two-storey rear extensions are permitted development, but side extensions over one storey always need planning permission.
Can you visit a house in Dagenham 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.
Other towns nearby
- Double-storey extensions in Becontree
- Double-storey extensions in Romford
- Double-storey extensions in Hornchurch
- Double-storey extensions in Barking
Learn more about double-storey extensions, or see every project we cover in Dagenham.

