Replacing a 1970s glazed infill, this intervention to the rear of a Victorian townhouse in the Primrose Hill Conservation Area of Chalk Farm reconfigures and extends a series of dark, cellular rooms into an unusually large inside space. Designing – and building – it was an almost surgical operation, introducing a very delicate, highly-detailed glass structure into a very confined area and cutting back the ground-floor slab to make a new vertical connection.

Views out are framed by oversized, yet proportionally fitting openings: a 5.5-metre-high door to the garden and vertically sliding sash windows that either screen or reveal.