Greenfield, Flitwick
This extensive 12-month project involved the complete refurbishment of a 1960s detached home in Flitwick, Bedfordshire. Transforming it into the first certified Passivhaus Plus retrofit in the UK. The renovation included a comprehensive redesign of the internal space. This featured a timber frame extension, the addition of a mezzanine and reorienting the roof to accommodate a roof-integrated solar PV system.
One of the major tasks was removing the existing ground floor slab to install extra insulation around the perimeter walls and lay a new slab. The new roof and timber frame were constructed using I-beam studs to minimize thermal bridging. The new floor was designed with Posi joists, allowing for MVHR (Mechanical Ventilation with Heat Recovery) ductwork to run through the first floor. The entire ground floor is equipped with underfloor heating, and due to the high level of insulation on the first floor, only electric panel heaters are required in the bathrooms.
The exterior of the house features Woodfibre insulation, complemented by Brimstone ash cladding on the first floor and render on the ground floor. This project also marked Apollo's first use of a Ground Source Heat Pump, which draws heat from coiled pipework buried in trenches in the garden.