Loft conversions in Barnet

Covering Barnet

We work in Barnet (EN5) and the places around it, including Potters Bar, 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 a loft conversion?

We start with the head height. You need roughly 2.2 m or more from the top of the ceiling joists to the underside of the ridge for a conversion to work without raising the roof. From there we design the staircase position, the type of conversion and the en-suite, and manage the whole build including fire safety and building control.

Loft survey and head-height check
Planning or lawful development certificate
Dormer or rooflights, insulation and plasterboard

How much should I budget for a loft conversion?

Indicative costs for loft conversions. London and the South East usually sit towards the top of each range.

Loft conversions	Guide price incl. VAT
Rooflight conversion	£30,000 to £45,000
Dormer conversion	£50,000 to £90,000
Hip-to-gable with dormer	£60,000 to £95,000
Mansard conversion	£65,000 to £110,000

What approvals does a loft conversion need in England?

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.

In England many loft conversions are permitted development: the extra roof volume must stay within 40 m³ on a terraced house or 50 m³ on a semi or detached house, nothing can sit higher than the existing ridge, no dormer can face a road on the main elevation, and side windows must be obscure-glazed and non-opening below 1.7 m. Houses in conservation areas, National Parks and National Landscapes cannot use these roof-extension rights, so dormers there need planning permission (a rooflight-only conversion can still be permitted development), and flats always need permission.

What should Barnet homeowners check first?

The new staircase usually takes space from the landing or a bedroom below.
Fire safety rules can mean new fire doors on the floors below.

What are the steps?

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.
Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
Construction and completion. One site lead co-ordinates every trade through to the building control certificate.

Loft conversions: common questions

Is my loft suitable for conversion?

If there is about 2.2 m or more from the top of the ceiling joists to the underside of the ridge, it usually is. We check this at the free site visit.

Do I need fire doors?

Often yes. Building regulations require a protected escape route from the new floor, which usually means fire doors on to the stairs and linked smoke alarms.

Can you visit a house in Barnet 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.

Also covering

Learn more about loft conversions, or see every project we cover in Barnet.