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.
Addresses across E4, E17, E18 and IG5 fall within our coverage for a double-storey extension, so if your home is in Woodford Green we can arrange a survey on a day that works for you. We inspect the existing building, discuss materials and layout, and then price the agreed specification in writing. Expect a guide range of £78,000–£156,000 including VAT before that visit.
- Guide price
- £78,000–£156,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- E4, E17, E18, IG5 and IG8
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
Double-storey extensions prices in Woodford Green
Use the table to gauge the cost of a double-storey extension in Woodford Green before we visit. Figures include VAT and are scaled for London, coming out about 30% above the national guide, which gives £78,000–£156,000 overall. After a free survey, you receive a fixed written price.
| Type of job | What it usually involves | Guide in Woodford Green |
|---|---|---|
| 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 |
Expect these to shape the final quote:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Bathrooms, en-suites and plumbing on the upper floor
- Scaffolding duration, access and the level of finishes
What’s included?
- Groundworks, foundations and below-ground drainage
- Insulated cavity walls with brick or render to match the house
- Roof structure tied into the existing roof, tiled to match
- Scaffolding for the full build, erected and inspected
- Electrics, plumbing and heating by qualified trades, with certificates
- Building control inspections and completion certificate
What are homes like around Woodford Green?
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.
If your house in Woodford Green fits one of these patterns, it helps us anticipate what a double-storey extension will involve, though we always confirm the details on site.
Do you need permission in Woodford Green?
England, Wales, Scotland and Northern Ireland each handle planning a little differently. Woodford Green comes under England, covered below, and we raise any questions with the council before your quote is finalised.
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.
The four stages
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
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Plan and prepare
Before anyone starts, we confirm the programme in writing, check whether consents are required and arrange deliveries. If a skip or scaffolding on the road needs a permit, we apply for it.
The work itself
During the work we protect the areas around it and tidy up at the end of each day. Once complete, we check the finish, remove our materials and hand over paperwork such as building control sign-off where it applies.
What you can expect from us
Common questions
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.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a double-storey extension, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
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.
Do I need planning permission for a two-storey extension?
Most two-storey extensions need planning permission, but it depends on the size, height and position, your home's location, whether it is listed or in a conservation area, and which UK nation you are in. In England, a two-storey rear extension can sometimes be built under permitted development if it is no deeper than 3m and at least 7m from the rear boundary. We check what applies before quoting.
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.
Near Woodford Green
We cover every part of Woodford Green, including E4, E17, E18 and IG5, and nearby Chingford, Walthamstow and Leytonstone. Wherever you are within that patch, the survey is free and the quote comes to you in writing.