For semi-detached houses, a hip-to-gable conversion is usually the clear choice.

The majority of London semis have a hipped roof on the side elevation, where the roof slopes down to the eaves rather than meeting a flat gable wall. Converting that slope into a vertical gable end creates the headroom and floor space needed to make the loft genuinely usable, and when combined with a rear dormer, it opens up enough room for a bedroom, bathroom, or home office with real comfort.

The conversion works by extending the ridge of the roof outward to meet the new gable wall, which gives the loft a noticeably larger footprint than a dormer alone would provide. It’s a well-established build that suits the proportions of a semi particularly well, since the side elevation is already set back from the neighbouring property rather than sharing a party wall at roof level.

Most hip-to-gable conversions on semi-detached properties fall within permitted development, so planning permission isn’t always required. Where it is, we handle the process alongside you: from getting your plans drawn up by our architect to submitting the application and managing the council’s response. Once approval is confirmed, work can begin. If you’d like to understand the planning process in more detail before committing to anything, our planning permission guide covers what to expect.