Mapesbury is stricter than most conservation areas in England. Brent council's Article 4 direction covers the whole area and takes away almost everything a house in an ordinary conservation area can do to its façade or roof without an application, so even roof-mounted panels and like-for-like windows here go through planning permission. Work inside the house and behind it is unaffected. For most residents the choice is narrower still, because nearly every home with a certificate in the area is a flat.
What Article 4 bans in Mapesbury and what is allowed without permission
Article 4 removes permitted development rights for solar panels and wind turbines on a house, replacing windows and doors, roof alterations such as rooflights, flues and chimneys, and painting the façade. In an ordinary conservation area, roof-mounted panels and replacing windows with similar ones need no permission; here they do. Everything else follows the general rules set out on our page on insulation in conservation areas: a heat pump at the back or side is fine, one on the wall facing the road needs permission; external wall insulation only with permission; internal wall insulation and loft insulation without any formalities.
Flats are trickier. A flat has no householder rights for these kinds of works, and almost any external work needs both permission and the freeholder's consent. An example: the owner of a top-floor flat wants panels on the roof slope. For a house in an ordinary area this would be permitted development; in Mapesbury, panels on a house need permission because of Article 4; and a flat has no householder rights at all, so there is only one route open: an application to the council and the freeholder's consent. For the single listed building (Grade II) in the area, listed building consent is needed as well.
The homes here and where the boundary runs
According to the EPC register, as at November 2026 the area has 1,591 homes with a certificate (the latest certificate per home; 59% were issued in 2020 or later), and 87% of homes are flats or maisonettes. Solid walls without insulation account for 78.6%, close to the figure for all 23 conservation areas in Brent (77.8%) and noticeably higher than the average across English conservation areas (48.7%). Some 75.4% of homes run on a gas boiler, 15 have heat pumps, single glazing survives in 17.9%, and bands D–G cover 65.2%. What those bands mean for price is shown in our comparison of EPC bands from A to G.
The area was designated a conservation area on 21 December 1982, it covers 48.3 hectares, and the most common houses here date from 1900–1929; Kilburn and Cricklewood are close by. The boundary on this site is the one current on 3 November 2026; if a house sits near the edge, the map and Brent council's conservation area appraisal decide. Neighbouring areas, such as Brondesbury and Willesden Green, are gathered on the page of Brent conservation areas. The rules here are national, as at 21 October 2026, and exclude building regulations; this is not a planning decision, so if in doubt ask Brent council.