Exemplar Sustainable Building Awards: Small project finalist: The Seed

Small project finalist in the 2025 Exemplar Sustainable Buildings Awards. Replacing a derelict building, The Seed is a co-living home for two households in a woodland garden near Dundee. The home is almost entirely timber and meets both Passivhaus Classic standard and RIBA 2030 embodied carbon requirements. It offers a shining example of how Passivhaus can work in locations with difficult site constraints and restricted solar gain.

The Seed was developed to carefully balance communal and private spaces for the two families co-living there. The existing house was in too poor a condition to be retrofitted but most of the existing building was reused or recycled within the construction of the new home. The woodland garden is covered by a Tree Preservation Order and the web of the mature tree roots restricted development, so careful design was needed to protect tree roots.

The project was built in off-site manufactured timber I joist frame, with recycled cellulose and wood fibre insulation. The house is built with steel screw piles foundation, to avoid the tree roots and to minimise the embodied carbon. Finishing materials include Scottish timber cladding and decking with zinc roofing. Reducing embodied and in use energy and carbon was a primary driver of the design and construction of the building and influenced every single decision.