Sharon Bhorkar

Evaluating the performance of domestic retrofits is essential in appraising their success and identifying if they improved the lives of occupants. In the UK, billions of pounds are invested annually in retrofits through policy funding, however, current building regulations do not mandate evaluation, and monitoring requirements are poorly defined. Without agreed standardised protocols or tools, retrofit evaluations remain inconsistent and incomparable, providing little assurance to occupants, landlords, installers, or the government. Post-occupancy evaluation (POE) is a common and well-established form of building performance evaluation (BPE) used in retrofit evaluations; however, it faces challenges in multi-dwelling retrofit schemes. This research evaluated the effectiveness of occupancy evaluation surveys in five domestic retrofit projects overseen by a local authority in Northern England between 2022 and 2024. Phase one implemented a retrofit survey taken from the UKGBCs BuildUpon2 Framework. In phases two and three, iterative improvements were made to the survey based on feedback from occupants and surveyors from the previous phases. Five key barriers were identified: resources, technical challenges, surveyor engagement, trust, and accessibility. Addressing these challenges increased the survey response rate from 25% to 98%. The refinements significantly improved the quality and usefulness of the data collected, offering valuable insights for designing robust, easily implementable occupant surveys.