Hybrid House

The project renovates the private home through upgrades and alterations to the interior, the creation of a single-storey rear extension at basement level, a roof extension over the side passage, and the construction of a separate garden room with an external pergola. The works were carefully developed within the constraints of its conservation area setting and listed status.

The rear façade has been opened at basement level to enable the formation of the modern basement extension, and a new outbuilding further extends the home’s floor plan. All existing upper floors were removed and rebuilt as part of the refurbishment, allowing the structural strategy to be rationalised throughout the house while retaining the primary loadbearing masonry shell. At basement level, existing loadbearing partitions were replaced with a ply-skinned truss wall, and the rear masonry is supported on a new timber beam bearing onto a stone pier, requiring careful temporary works and sequencing during construction.

The new structures employ a hybrid timber and stone solution. The project represents the first built example of this composite approach, translating earlier research and prototyping with The Stonemasonry Company and other collaborators into a permanent residential setting.

The roofs are formed of timber joists with stone infills, spanning into a timber beam, then supported off a stone column. In the rear extension, the roof is additionally supported by a post-tensioned stone beam, designed to achieve the required spans and control deflection while expressing the stone structurally. The stone beams were detailed with stainless steel tendons and grout-filled joints to mobilise flexural capacity, with long-term deflections carefully limited to protect adjacent masonry and glazing interfaces. The garden room adopts a similar structural language, with a suspended concrete ground slab on pad foundations and a timber and stone roof structure above.

The structural design is deliberately legible within the rejuvenated home, pairing low-carbon materials with precise detailing so that architecture and engineering resolve as a single, coherent whole.