Architects Tom and Elizabeth Miller of Haysom Ward Miller – winner of House of the Year 2018 – turned the 65 sqm Suffolk Cottage near Bury St Edmunds into a 160 sqm, three-bedroom home for themselves and their two daughters. The flint-walled labourer’s cottage has been stabilised and retained, with an insulated timber-frame box extension that helps to brace the original walls.

The project was one of the top three House of the Year 2022 submissions for energy performance. Thanks to the substantial contribution from photovoltaic panels, Suffolk Cottage addressed the RIBA 2025 benchmark for energy use. Crafted with modest resources, it has an air-source heat pump, triple glazing and a mechanical ventilation with heat recovery system.

Judges also commended the build for the low embodied-carbon materials used, including the reuse of materials wherever possible. The new external masonry is made from reclaimed surplus bricks and flint blocks, while the new addition has triple-glazed windows and roof lights, plus internal finishes including bamboo panels, vegetable oil-based plywood, natural linoleum, reclaimed undyed wool carpet, self-coloured plaster and zero-VOC paints.

Architectural designer Martin McCrae and architect Mhairi Grant, who run Paper Igloo, designed and built the very first certified Passivhaus in Stirlingshire, Scotland. They project, which they built for themselves, was an eight-year labour of love crafted to the exacting standards of Passivhaus certification.

Named after a southerly wind in the Adriatic, Ostro is a double-height, south-facing, Siberian larch-clad ‘box in a box’ on a timber frame. Built in a conservation area, the Passivhaus is highly insulated with wood fibre to create a continuous thermal break. There are solar and photovoltaic panels on the roof, while the orientation and balanced proportion of the triple-glazed windows maximise views and minimising the risk of overheating in the summer. The doors are insulated with aluminium.

A central two-storey black-timber cube that contains all the service spaces is reminiscent of the entrance to Charles Rennie Mackintosh’s Hill House. Within this cube are clever storage ideas like drawers in the steps and a gin store next to the kitchen worktop. Careful consideration was also given to the embodied carbon of each of the carefully selected materials, both inside and out.