According to a recent study, “The Impact of Green Buildings On Cognitive Function”, certified green buildings improve human health and cognitive abilities compared with similar buildings that are not certified.
The study, carried out by researchers at the Harvard University T.H. Chan School of Public Health’s Center for Health and the Global Environment and SUNY Upstate Medical University, analysed 109 workers in 10 high-performing buildings across five U.S. cities.
Workers in Denver, Colorado, San Jose, California, Los Angeles, California, Boston, Massachusetts, and Washington, D.C. were studied for one week, with testing for cognitive function taking place on Tuesday and Thursday. Strategic Management Simulation (SMS) software was used for testing cognitive function.
All 10 buildings were classified as high-performing buildings as defined by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) under the group’s standard for low total volatile organic compound (TVOC) concentrations and acceptable ventilation and indoor air quality. Only 6 of 10 were LEED certified, however, and workers in those buildings showed improvement across a range of metrics. According to the study, the greatest cognitive function differences were as follows:
- Crisis response scores were 73 per cent higher.
- Applied activity level, “the ability to gear decision-making toward overall goals”, was 44 per cent higher.
- Focused activity level, “the capacity to pay attention to situations at hand”, improved by 38 per cent
- Strategy improved by 31 per cent.
In addition, researchers tracked participants’ sleep quality with wearable monitors, finding a 6.4 per cent improvement in workers in the certified buildings. Participants also completed daily surveys that evaluated their health and environmental perceptions and tracked the occurrence of 19 “sick-building” symptoms. A different survey on the final day assessed the participants’ satisfaction with the indoor environment, including odors, lighting, thermal comfort, and noise.
According to the researchers, the improvement in cognitive function and sleep scores in certified green building can be partially explained by difference in lighting and thermal comfort. However, the findings suggest that measurable indoor environmental quality factors play only a partial role, and that green-certified buildings offer something more.
To tease out additional factors, the study team recommends an approach to building design and construction they call Buildingnomics, which they define as “The totality of factors in indoor environments that influence human health, well-being, and productivity of people who work in those spaces.”
This is the second study in the series. In the first study, participants scored double in cognitive function tests in a simulated green building environment with enhanced ventilation compared to conventional buildings.
In addition to improving human cognition, green-certified buildings can also play a role in enhancing and maintaining human health. The WELL Building Standard, for example, emphasizes healthy design elements such as pure air and water, access to the natural environment, and creating quiet, soothing, distraction-free workspaces. Providing comfortable, easy-accessible stairways encourages people to forgo using the elevator and move their feet.
The World Green Building Council has also issued a report, “Health, Wellbeing, & Productivity in Offices”, that, similar to the Buildingnomics study, examined green-building features that also offer benefits to occupants. The study emphasized the cost of staff salaries and benefits to businesses—typically around 90 per cent—to show building owners and managers the importance of providing health and productive spaces for employees.
The report emphasizes the following factors in creating offices:
- Indoor air quality
- Lighting and daylighting
- Thermal comfort
- Interior layout
- Look and feel
- Active design & exercise
- Amenities & location
“There are reputable, robust studies that suggest the green design features of buildings lead to healthier, more productive occupants,” the study noted.