Loft conversion in Hammersmith and Fulham

Often not a full application outside the conservation areas — rear dormers within the volume limits (40m³ terraced / 50m³ semi-detached) can proceed under permitted development with building regulations approval. Inside a conservation area, Class B rights are removed and a full application is needed, with dormer form and roofline under scrutiny. Flats always need permission.

Rear dormers approve on many terraces under PD; conservation-area rooflines need a full application.

The Victorian and Edwardian terrace stock across Fulham and Hammersmith converts readily where headroom allows, and rear dormers are a routine project on unconstrained streets. On conservation-area streets the same roof change becomes a design argument: rear-facing dormers that sit back from the eaves and leave the principal elevation alone have the stronger record; box dormers and front-facing alterations are the classic refusals. Building regulations — stair geometry, fire escape, floor structure — apply whichever planning route you take.

Permitted development (GPDO Class B) allows roof enlargements up to 40m³ on terraced houses and 50m³ on semis and detached — enough for a substantial rear dormer — provided nothing projects beyond the roof plane of the principal elevation, materials are similar, and dormers sit back from the eaves. Class B is excluded in conservation areas.

In conservation areas the route is a full application, and roof form decides it: rear mansards with traditional slate and proportioned dormers have a strong record on Victorian terraces; box dormers and front-facing alterations are the classic refusals. Article 4 directions (Muswell Hill is the local example) pull roof works into planning control even where conservation policy alone might not.

Whatever the route, building regulations approval is always required — fire escape, stair geometry and floor structure — and a Lawful Development Certificate is cheap insurance on PD schemes.