The muscular streetwall of Wimpole Street typically comprises terraced houses of 5 storeys plus a set-back mansard roof level. Today, most of this Georgian architecture is occupied by medical practices and associations but some houses survive as private residential homes. Our clients acquired the upper 3-storey maisonette within one such Grade II listed house that was missing the mansard floor.
With a brief to modernise and expand the flat, within the demanding heritage environment, Robert Dye Architects was able to substantially remodel the property and to add a mansard level.
Research showed that a Surveyor had added a floor to the house in the 1980s. But disappointingly, with the direction of the staircase switched from longitudinal on the first floor to transverse on the second and third floors. this resulted in little sense of internal connection between any of the floors and a strong vertical division of the upper floors, worsened by a rabbit-warren configuration of bathrooms around the transverse stairs at the top.
Refining the brief with the client to suit the circumstances, the big move became to open up the house with a new circulation void rising through the upper floors to connect to the new mansard level. Lower down, this allowed reconfiguration in the vertical and horizontal. The original lift was in very poor state and only went to the First Floor. With a client intending to enjoy retirement in this home, the lift was replaced and extended upwards to reach the Master Bedroom floor. The new walnut open-tread stairs improve light penetration and the stair void is day-lit from the new roof level.
Whereas the main task on the 1st floor was to freshen up the large historic rooms, the 2nd and 3rd floors were reconfigured around the new staircase. The space freed up in the middle of the plan provided a large hall with which to connect the rooms. The staircase is at one end and ‘wet’ spaces are stacked on the other, clearly defining the hierarchy between the functional spaces and returning legibility to the whole.
Having lived abroad extensively in hot sunny climates, our client was keen to integrate outdoor space into the overall layout. This was quite a tall order in the restricted and dense urban situation. Although the flat had a small back terrace off the 1st Floor kitchen, it was clear that they needed a sky-space at the very top. Studies showed the best sunlight and views were to the street front, but Westminster Planning guided the design towards the opposite – a traditional mansard roof rising behind the front parapet!
The solution was to leave the sloping mansard but remove the flat roof at the front to reveal an outdoor room. Thus the terraced sequence of mansards in the street is completed whilst providing the client with generous outside space open to the sky, sun and views across London yet sheltered from wind and overlooking. The roof level is considered as one large living floor with its own kitchenette.
Contractor: ShipShape Construction Ltd.
Structural Engineer: Greig Ling
Quantity Surveying: Nigel Ray Associates
Photography © Robert Dye Architects & © Gabriel Haidau