One of a series of similar late 1920s detached houses on a curving street in Dulwich Village, the original building appeared to be both generous in plot and accommodation. In reality the plot quickly tapers from a broad frontage to leave a surprisingly small garden to the rear. Similarly, whilst not small, the ground floor lacked scope for reconfiguration and ‘standard’ extension formats wouldn’t suit.

Through careful investigation and collaboration with both engineer and contractor we cut away one rear quarter of the house and excavated this footprint and out to the south boundary to create a semi-basement space providing a cinema games room (that doubles as a guest bedroom), laundry and wine cellaring. A layered stone stepped lightwell rises to the rear garden and is the setting for a 3m tall, 4m wide ‘waterwall’ feature, bathing the garden in the soothing sound of running water. The stonework is continued to form a new base to the house and runs in to the kitchen and dining room. Large ground floor spaces have been formed over the basement by building right out to the south boundary and projecting forwards of the front elevation to frame the driveway.

The new accommodation is completed with reimagined first floor bedroom suites and the insertion of the loft bedroom suite into an unusually low roof space.

These ground floor extensions are clad in a finely profiled timber, using thermally modified English ash hardwood. This has given the building the feel of a piece of refined joinery, in comparison with typical timber cladding. Thermal modification is a process of heat curing that results in the wood being more stable (less susceptible to warping) and lasting longer. The timber started as a chocolatey brown, similar to an adjacent yew tree trunk and is gently changing to silver, connecting the house to the paler tones of the existing building.

Throughout the house, timber joinery punctuates and frames spaces providing both vital storage and a warm character, continuing the theme of welcoming details found in the existing hallway painted panelling. Special moments are the ash veneered wardrobes, doors and panelling to the primary bedroom suite, completed with a rich Carrara marble clad bath and shower room, and a bijou home office hidden at the front of the former garage behind the original garage doors, which open as shutters to reveal the glazing at the press of a button.