This proposal involves the extension and retrofit of an existing mixed-use building, including a new basement, reconfigured residential layout, and a loft conversion with a flat-topped mansard roof to create an additional one-bedroom apartment. The basement extension will improve staff facilities for the pharmacy, while the ground floor will benefit from an expanded footprint and new thermally efficient glazing. Above, the residential units are reconfigured to meet London Housing Space Standards, and the new mansard roof adds a well-designed apartment suitable for a single occupant or couple.