# Builders in Willesden

Canonical URL: https://mirion.uk/areas/brent/willesden/

> Loft conversions, extensions and renovations in Willesden, Willesden Green and Mapesbury: Victorian houses, flats in converted houses and Brent planning rules.

We work on Victorian and Edwardian houses across Willesden, Willesden Green and Mapesbury: loft conversions, rear and side-return extensions, and full renovations of houses that are often more than a century old.

Willesden grew around its railways. The Metropolitan Railway opened Willesden Green station in 1879, and in Mapesbury, just to the east, building lots were let for “first class residences”: most of its brick-built houses went up between 1895 and 1905, with extensive tree planting. After the First World War, Willesden grew quickly again as factories opened, bringing smaller terraced houses and flats.

Many of those houses have since been divided. In the 2021 Census, only 26% of households in Willesden Green, Dudden Hill and Brondesbury lived in a whole house, and almost a third lived in flats within converted houses. Median semi-detached prices in those areas were about £900,000 to £1.1 million in the year to March 2026.

For whole houses, the common projects are rear dormers and L-shaped dormers over the back addition, side-return infills and kitchen extensions. In converted houses, the space is usually in the top-floor flat's loft or the ground-floor flat's garden, and both need full planning permission.

Willesden is in Brent. Outside conservation areas, the council's 2025 SPD accepts L-shaped dormers over an outrigger if they cover no more than half of its depth and sit at least 0.2 metres above the eaves, and extensions to outriggers of up to 3 metres beyond the outrigger's end wall.

Two conservation areas cover much of the best Victorian housing here. Mapesbury, designated in 1982, has both an immediate and a non-immediate Article 4 direction, and Willesden Green has a non-immediate direction. Inside them, roof alterations, windows and front boundaries are controlled more tightly, and the conservation area design guide applies instead of the general SPD.

Flats and maisonettes have no permitted development rights for extensions or loft conversions, so if your home is part of a converted house, plan on a full application and on agreeing the work with the freeholder and other leaseholders.

Building work in Willesden: common questions

Can I extend a flat in a converted Willesden house?

Yes, but always with a full planning application, because flats don't have permitted development rights for extensions or roof enlargements. You will also need the freeholder's consent under your lease and, usually, party wall notices to the neighbouring properties.

Is Mapesbury a conservation area?

Yes. Mapesbury was designated a conservation area in 1982 and has Article 4 directions, so roof, window and front garden changes that are permitted development elsewhere can need permission. The Willesden Green conservation area also has a non-immediate Article 4 direction.

- Local planning authority: London Borough of Brent
- Postcode districts: NW2, NW10
- Work Mirion has carried out here: Extensions, loft conversions and renovations