Lansdowne Road by Mulroy Architects

A two-phase whole-house renovation in Muswell Hill, north London, that grew the family home by 25 per cent without disturbing the original Victorian bay window at the rear.

The brief was to maximise every usable square metre across the property while preserving the architectural quality of the existing rear living room. Mulroy Architects' answer was to detach the new rectangular extension from the existing house and bridge the gap with a courtyard. Because the building's width would have left the linking kitchen uncomfortably narrow, the courtyard wall became a frameless curved glass screen drawn around the original bay. The reference, openly cited, is SANAA in Japan.

The curve does two things at once. It widens the dining area as it bends, and it pulls a clear sightline from the front door through to the rear garden. The bay window is no longer a wall at the back of an extension; it becomes the focus of the new dining space, lit from both sides by the glazed courtyard. The courtyard itself reads as a private outdoor room that the neighbours cannot overlook.

Phase 1, completed in 2009, added the loft. A new staircase, a loft bedroom with a view towards Alexandra Palace, a study carved out of the eaves, and a bathroom squeezed under the gable. Phase 2 added the ground floor extension, the curved courtyard and a first floor study with a corner window framing the garden. The flat green roof is finished in sedum so first floor neighbours look down onto planting rather than felt.

Project size 67 m². Site 100 m². Completion 2020. Two storeys plus loft.

Architect: Mulroy Architects. Photography: Dan Glasser (Phase 2) and Will Pryce (Phase 1).