A two-year post-occupancy performance evaluation has been undertaken of the apartments within Galliard Homes’ Seager Distillery redevelopment site in London. The Seager Distillery site is typical of the many new high-density developments in London, reflecting the tightening standards on energy use and pressure on land use. This paper presents the energy and environmental performance of three apartments studied in detail, including the assessment of the performance of the building fabric, MVHR units and the communal heating system.

The paper compares the actual performance against the design intent of the apartments and summarises the performance of the communal heating system in use. It then highlights the reasons for any performance gaps identified, which provide useful learning to both Galliard Homes and the wider building industry.

The study has demonstrated that measurements of the actual performance of the building fabric align with design expectations; however, issues were found in the performance of the MVHR systems in the apartments affecting thermal comfort and energy use. This was further exacerbated by the underperforming communal heating system, where various shortcomings have affected its design, installation and operation.

The study highlighted areas for improvement in the building and its services in terms of design, installation, commissioning and post-occupancy maintenance. Better building handover and occupant access to relevant information were identified to promote building usability and further contribute to closing the performance gaps.