Client's Brief and Planning Constraints
Following the redevelopment and conversion of Southwood Hospital in 2003 to form six terraced townhouses, each with private gardens, a significant area of unused land remained. The client's brief to the architect was to design and secure planning consent for a large house for single family use on this land.
The site is within the Highgate Ridge Conservation Area and was originally a registered historic park. A number of mature specimen trees surrounding the site still exist and the site is overlooked by a tall apartment building. Due to these constraints, the planning officers fom Haringey Council were sceptical that any building could be accommodated within the site without detrimental impact on the Conservation Area, the outlook from adjoining properties and the existing trees.
To take full advantage of the steeply sloping topography, the architect designed the house to be cut into the site and buried under an intensively planted green roof, thereby making the building almost invisible when viewed from the surrounding properties. Only the south and east elevations are visible and then only from within the site itself. This ensures that the house does not overlook adjoining dwellings or their gardens and also that the house itself is not overlooked. The house is ideally situated within the site to allow a large amount of open land to be retained, which has been sensitively landscaped as a garden. All existing trees have been retained
and have been fully considered as part of the design strategy.
Design, Materials and Construction
Formal in its plan and elevation, with large areas of glazing to the principal east elevation, the house is a contemporary interpretation of a classical garden pavilion. The central projecting bay was conceived as a double-height glazed cube and contains the formal reception room with master bedroom above as a floating mezzanine. The circulation spine to the rear of the house is designed as a gallery and is terminated at each end with a top-lit, double-height cube; one being the entrance hall, the other being the library. The two side wings contain the ancillary and subsidary bedroom accommodation. These wings are splayed so as to terminate the elevation and provide clarity in both form and the way in which they encompass and define the garden.
The main structure of the building is concrete, giving high thermal mass floors, walls and ceilings to provide natural heat storage and insulation, offering minimal fluctuation of internal temperature throughout the year. The building is also partly earth-sheltered, being sunken into the ground and having the intensive green roof. These innovations reduce the requirement
for additional heating and cooling.
The external walls have floor to ceiling windows and are clad with natural stone tiles. The windows and doors are natural timber and the projecting eaves are strainless steel. The roofs are above the central bay and the entrance hall and library cubes are covered with lead.
Renewable energy sources within the site include an array of south-facing photovoltaic cells and a ground array heat pump, the coil of which is buried behind the precast concrete retaining wall. There is also a heat recovery ventilation system and grey water recycling.