Optimised indoor air quality and thermal comfort for primary school classrooms : a New Zealand case study : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy (PhD) in School of Built Environment at Massey University, Auckland, New Zealand

Abstract

In the wake of the COVID-19 pandemic, the critical importance of indoor air quality (IAQ), thermal comfort (TC) and ventilation in school spaces has gained unprecedented relevance. This research, initiated in 2020 at Massey University, Auckland, New Zealand, strategically coincided with the global reconsideration of indoor environment norms and guidelines, providing a timely opportunity to establish comprehensive frameworks for evaluating school environments in New Zealand primary schools. Schools function as second homes where children spend approximately 13,000 hours throughout their academic journey, with up to 90% of their developmental years in indoor educational environments. This extensive indoor exposure makes the quality of school environments particularly consequential for students' physical and mental development. Despite this significance, New Zealand primary schools predominantly rely on natural ventilation systems, often limited to manual window operation, raising concerns about consistent environmental quality maintenance, which often raises concerns about poor IAQ and TC presence within the indoor environment. While the Ministry of Education (2022), has established the Designing Quality Learning Spaces (DQLS) document as a framework for school design standards, significant gaps remain between these guidelines and the practical reality in many classrooms. The current DQLS guidelines provide minimum mandatory requirements for IAQ and TC, tailored to New Zealand's diverse climate zones. Furthermore, the COVID-19 pandemic has highlighted additional ventilation needs for reducing viral transmission risks that have not been fully addressed in existing DQLS versions. This research investigates these shortcomings in the current DQLS framework. This study employs a multi-stage methodology using a mixed-method approach. First, it compares the evolution of Designing Quality Learning Spaces (DQLS) guidelines from version 1.0 (2017) to version 2.0 (2022), establishing the current regulatory context. Second, it conducts content and document analyses comparing DQLS v2.0 with international benchmarks, including WHO, ASHRAE 62.1, CIBSE TM 57, EN-15251, and Building Bulletins 99 and 101. Third, it performs detailed simulation studies across six diverse climate zones of New Zealand using two representative primary school typologies, namely Avalon Block and Canterbury Block, examining multiple parameters, including temperature, relative humidity, ventilation rates, carbon dioxide levels, window-to-wall ratios, occupant density, classroom dimensions, and ventilation strategies. Finally, it incorporates industrial validation with experts in school designing, architects, building scientists, and facility managers through qualitative and quantitative analyses via open-ended and Likert scale questionnaires for findings and design changes to develop optimal IAQ and TC guidelines for New Zealand primary school classrooms for the post-COVID-19 environment. The research addresses critical gaps for New Zealand primary schools, where high occupancy density, infrequent facility inspections, and simple ventilation mechanisms create vulnerable conditions, especially in the post-pandemic context when extended school closures created conditions potentially favourable for the accumulation of indoor pollutants while simultaneously increasing awareness about transmission risks. By connecting established knowledge about IAQ and TC impacts with the new pandemic context, this research provides timely insights for educational facility management, public health policy, and pedagogical practice in ensuring optimal learning environments for students, teachers, and caregivers during their most formative years. This work contributes significantly to understanding how learning environments can be designed to support health and educational outcomes in a world transformed by pandemic awareness.