8-12 William Street is a Grade II listed terrace comprising commercial use at two lower levels and residential apartments on floors above. The Client has a track record of bringing a new lease of life into historic properties by adapting them to the requirements of modern uses and significantly uplifting their appearance. The redevelopment aims to increase the commercial floor space and enhance the overall appearance of the building. The commercial units were enlarged through the addition of a sympathetic rear extension at lower levels of the building, while their street presence was enhanced by reinstating traditional shopfronts. Two overbearing external staircases were removed at the back. The rear elevation was stripped of layers of haphazard additions and services which accumulated over the years to reveal its historic form and character. The residential amenity was upgraded through the reconstruction of balconies and the introduction of a new green roof. The previously disorderly backyard was transformed into a well-maintained oasis of tranquillity enclosed by a green wall. New green roof and preamble paving contribute to improving sustainability and biodiversity.