A double-storey extension adds two floors of new space to your house in one build, typically a larger kitchen or living room downstairs with an extra bedroom, bathroom or en-suite above, sharing one set of foundations and one roof.
Edmonton sits within our coverage for a double-storey extension, as do neighbouring Tottenham, Enfield Town and Chingford. Before giving a price we want to see the property: the condition of what's there now, the access, and anything that might need extra work. The guide range for London is £78,000–£156,000 including VAT, and your written quote will spell out exactly what that covers.
- Guide price
- £78,000–£156,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- EN1, N9, N13, N17 and N18
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
What should you budget for a double-storey extension in Edmonton?
Prices for a double-storey extension vary from house to house, but in Edmonton most projects fall within £78,000–£156,000 including VAT. That reflects costs in London, about 30% above the national guide. Treat the table as a budgeting aid; the written figure follows a survey we carry out for free.
| Type of job | What it usually involves | Guide in Edmonton |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £52,000–£84,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £78,000–£156,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £130,000–£234,000 |
The main things that change the figure:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Bathrooms, en-suites and plumbing on the upper floor
- Foundation depth, ground conditions and drains to divert
What’s included?
- Insulated cavity walls with brick or render to match the house
- First-floor joists, stud walls and new openings upstairs
- Scaffolding for the full build, erected and inspected
- Electrics, plumbing and heating by qualified trades, with certificates
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
What are homes like around Edmonton?
London's housing is dominated by Victorian and Edwardian terraces, often in yellow London stock brick, with Georgian terraces in central districts and mansion blocks across many inner areas. Outer boroughs have large belts of interwar semis, and there are extensive post-war council estates. Many houses have been split into flats, and conservation areas are widespread.
Terraces suit side-return extensions and rear dormer loft conversions; interwar semis commonly take hip-to-gable lofts. Shared party walls, restricted parking and conservation rules often shape the plans and the programme.
Building traditions across London also raise conservation and planning questions, so we check those for a double-storey extension in Edmonton at the survey stage.
Do you need permission in Edmonton?
Edmonton is in England, so the planning and building rules set out below are the ones that apply. We confirm the details with the council before we quote.
In England, a two-storey rear extension can only be permitted development if it is no more than 3 m deep, at least 7 m from the rear boundary and finished to match the house. Most double-storey and all two-storey side extensions need full planning permission.
Building Regulations approval is needed, with structural calculations for beams, foundations and the roof. The Party Wall etc. Act 1996 often applies on semi-detached and terraced houses.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
From survey to handover
We look at the job
We arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a double-storey extension so the price reflects your home.
Price and scope agreed
You get the price in writing, itemised so you can see where the money goes. As long as the specification stays the same, that is the price you pay for a double-storey extension.
Dates and permissions
With the quote agreed, we book the work in and handle preparation: permissions where needed, building control notifications, material orders and access arrangements for your Edmonton property.
On site to finish
The work is carried out to the agreed specification, with floors and furniture protected and the site kept tidy. At the end we clean up, walk through the finished job with you and hand over any certificates.
Why homeowners choose us
Double-storey extensions in Edmonton: questions
Can the new upstairs room have its own bathroom?
A new upstairs room can usually have an en-suite, provided waste pipes can reach the soil stack or a new one can be installed. Running the waste pipe to the right falls is the main design question, and a pumped system is an option where gravity will not work. We plan bathroom positions at the design stage so pipes, ventilation and insulation are built in rather than added later.
Can we live at home while it is built?
Most families stay at home during a double-storey extension. The new structure is built outside first, and we only break through into the existing rooms near the end, usually one floor at a time. Upstairs, this may mean a bedroom is out of use for a week or two. We fit dust screens, protect floors and stairs, and plan any time without water or power in advance.
Is the price fixed?
Yes, for the specification we agree. Your written quote sets out exactly what is included at a fixed price. It only changes if you ask for something different, or if a problem the survey could not reasonably reveal later needs extra work. In either case we explain the change and confirm it in writing before going ahead.
Do I need planning permission in Edmonton?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Edmonton is in England, so England's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
Will the extension affect my neighbours?
A double-storey extension can affect neighbours' light, outlook and privacy, which is why planning departments look closely at height, depth and window positions. Side windows facing neighbours often need obscure glass. Work near a shared wall may also need party wall notices; the Party Wall etc. Act 1996 applies in England and Wales only. We talk through these points early so the design is realistic.
Near Edmonton
We cover every part of Edmonton, including EN1, N9, N13 and N17, and nearby Tottenham, Enfield Town and Chingford. Wherever you are within that patch, the survey is free and the quote comes to you in writing.