More-or-less public, more-or-less private, the Georgian townhouse is London’s most hard working architectural typology. We pushed it to its limits, adapting the typology to provide a mixed-use socially sustainable development that provides commercial spaces, residential accommodation and a three-storey family home. The project includes a full-scale renovation, reorganisation and reinterpretation of the existing building; a three-storey cantilevered rear extension; and a light-weight roof-top pavilion and garden with brushed stainless-steel architrave and framed views of the London skyline. We enjoyed the opportunity to use architecture to support a mixed-use urban environment and to experiment with central London’s essential urban tissue.