Working alongside project leaders Calum Duncan Architects, the structural engineering approach centred on integrating new structural elements with the original building, believed to be designed originally by architects Mactaggart and Mickel.
A key advantage at the outset was the full strip out of the existing property, which provided clear visibility of the original structure. This allowed detailed assessment of the existing load paths and condition of the fabric, enabling the design team to develop a precise structural strategy.
The new extension required a structural solution that delivered open plan living at ground floor level, with a kitchen and living space arranged to maximise natural light and views to the garden. To achieve this, steel beams were introduced to support new floor loads while removing internal walls and ensuring lateral stability. The upper floor, containing two additional bedrooms, utilised a combination of engineered timber and steel to achieve long spans and minimise the impact on the existing structure.
Concrete foundations were designed to support the increased footprint, tying into the original foundation layout while accounting for variations typical of 1960s construction. The external walls of the new extension were formed using a highly insulated timber frame, improving overall thermal performance and supporting the architectural intent for a high quality Russwood timber cladding finish.
The integration of improved insulation, triple glazed windows and an air source heat pump required careful coordination with the structural design to maintain airtightness and accommodate increased wall build ups. The re-cladding of the existing side garage also required assessment of the substrate and limited structural upgrades.
The completed extension provides a contemporary, structurally efficient addition that respects the character of the original house while significantly enhancing its performance and spatial quality.
