The property is a narrow 3 bedroom second floor apartment set within a 6-storey imposing early 20th century period mansion block in Knightsbridge. The original layout was characterised by its long featureless corridor with doors leading to rooms on one side, and the kitchen and living/dining room at opposite ends. Our aim was to transform this dull procession route with features and focal points that give hints to the spaces beyond as well as letting daylight into the corridor. The long hallway was shortened by reordering the rooms to create a much bigger kitchen, living and dining room at one end with hidden fire doors to open up the vista as one enters the apartment. The filler joist construction of the building poses structural challenges to the transformation which was overcome by efficient design of the temporary and permanent steelwork in close coordination with the architectural requirements.