Covering Barnet
Barnet is about 10 miles north of London. We also cover Potters Bar (3 miles to the north), Borehamwood and Finchley.
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 goes into an upward extension?
The first question is whether the existing walls and foundations can carry the extra load, so we start with a structural survey. Then we design either a full first floor or a raised roof with dormers, handle planning or prior approval, and build the new storey while protecting the floor below.
- New first-floor structure, walls and roof
- Staircase and changes to the ground floor layout
- Full fit-out of the new rooms
What will an upward extension cost?
Guide prices for bungalow and upward extensions, including VAT where it applies. Your fixed price is confirmed in writing after the survey.
| Bungalow and upward extensions | Guide price incl. VAT |
|---|---|
| Chalet conversion with dormers (total) | £45,000 to £85,000 |
| New first floor, standard specification | £2,200 to £2,800 per m² |
| New first floor, good specification | £2,800 to £3,300 per m² |
| New first floor, high specification | £3,300 to £3,800 per m² |
What approvals does an upward extension need in England?
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
In England, Class AA permitted development allows an extra storey on many detached and semi-detached houses built between July 1948 and October 2018, subject to a prior approval application covering design, neighbours’ amenity and other matters. Houses in conservation areas and other protected land need full planning permission, as do most chalet conversions with front dormers.
What should Barnet homeowners check first?
- The house is exposed while the roof is off, so the sequence is planned tightly.
- Neighbours’ light and privacy are the main planning tests.
How does the project run?
- 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.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
What people ask before starting
How much does it cost to add a storey?
Around £2,200 to £3,800 per square metre of new floor including VAT, or £45,000 to £85,000 for a chalet conversion with dormers.
How long does it take?
About 12 to 24 weeks on site.
Do you work in Barnet?
Yes. Barnet is within our coverage for bungalow and upward extensions, along with nearby Potters Bar and Borehamwood.
Also covering
- Bungalow and upward extensions in Potters Bar
- Bungalow and upward extensions in Borehamwood
- Bungalow and upward extensions in Finchley
- Bungalow and upward extensions in Muswell Hill
Learn more about bungalow and upward extensions, or see every project we cover in Barnet.