Breathing easy


Architype researcher Chryssa Thoua DiplArchEng MSc MRes undertaking post occupancy evaluation

The quality of air we breathe is fundamental to our health. A World Health Organisation report in 2018 highlighted how pollution can have a particularly adverse impact on children, whose lungs are still developing, with the UK having the highest prevalence of childhood asthma among all European countries.*

As well as pollutants, other factors such as temperature and levels of fresh air (using CO2 concentration as a proxy for fresh air) can have a major impact on children’s learning, so a holistic look at indoor environments is required. 

Architype’s previous research into Passivhaus schools (the KEEN project with Coventry University) highlighted how the Passivhaus approach achieved very stable temperatures, excellent levels of CO2 as well as ultra low energy consumption. 

Architype researcher Chryssa Thoua undertaking post occupancy evaluation

Chart shows the stable summer temperatures of Architype’s Passivhaus
schools compared to a conventional 1970s building 

Graph shows the lower levels of CO2 achieved in Architype’s Passivhaus
schools compared to a typical 1970s school, which in some cases exceeded
the Building Bulletin 101 school design standards 

While this research has proved invaluable in constantly improving performance in our Passivhaus schools, there was a lack of evidence for broader air quality indicators that are so vital in children’s health.

To fill this gap, Architype’s researcher Chryssa Thoua has been undertaking a doctoral research degree supported by Architype and the Engineering and Physical Sciences Research Council at University College London’s Institute for Environmental Design and Engineering. The in-depth four year study is nearing its conclusion in March 2021. The research comprehensively assesses a complex range of metrics in four of Architype’s Passivhaus schools, comparing the results to UK Sinphonie (Schools Indoor Pollution and Health: Observatory Network in Europe) data to understand how Passivhaus schools perform in comparison to other building types.

The research looks at temperature, relative humidity, carbon dioxide and pollutants including particulate matter, nitrogen dioxide and total volatile organic compounds (VOCs). As well as remote monitoring systems, Chryssa spent two weeks in each school, during summer and winter because of the wide variance in results between the two seasons. As well as extensive scientific analysis in UCL laboratories, the up-close observations in three classrooms in each school allowed variances in classroom occupancy, location and orientation to be taken into account when interpreting the results.

Some of the monitoring equipment used in classrooms
and around the schools during the research

The schools chosen for the study include an inner London school, a rural school in Wales and two suburban schools in Wolverhampton. Questionnaires for teachers and students tracked perceived indoor air quality and thermal comfort as well as levels of user control over the indoor environment.

 “I hope the research will provide a framework for properly assessing indoor air quality in all schools and address the lack of evidence and benchmarking there currently is in this area.” Chryssa comments.

“This research will help to shape policy and hopefully mean that new standards are set, protecting the health of children. 

“It will also provide insights for schools and school designers as pollutants don’t only come from external sources like traffic – indoor sources such as the choice of cleaning products, paints, building products, teaching materials, floor coverings and furniture can all impact the quality of classroom air. As VOCs have been linked to carcinogenicity in humans, data from the research has reinforced the need for architects to specify natural non-toxic materials that will limit our exposure to pollutants.” she concludes.

Other insights are likely to highlight how differences in window design and ventilation systems can impact on classroom environmental quality. For example, designers have the opportunity to reduce traffic-related particulate matter with mechanical ventilation in airtight Passivhaus schools, and to better understand the conditions for good air quality.

As the results are calibrated they are highlighting how much more we have to learn on this essential subject – emphasising the importance of us all going back to school to improve results.

* Reference: