Green Buildings and Health

Abstract

40 years of public health research on buildings has identified the indoor environmental drivers of health and productivity. Concurrently, increased environmental awareness spurred the green building movement with the goal of encouraging more sustainable buildings. The question remains as to whether green buildings are also healthy buildings.

The objective of this dissertation is to investigate the impact of green buildings on health and cognitive function in both laboratory and real-world settings, and furthermore quantify these impacts in comparison to the potential environmental and economic costs. First, 24 participants spent 6 work days in a controlled office environment. On different days, they were exposed to conditions representative of Conventional (high volatile organic compound (VOC) concentration), Green (low VOC concentration), and Green+ (low VOC concentration and increased ventilation) office buildings. Additional conditions tested artificially elevated carbon dioxide (CO2) levels. On average, cognitive scores were 61% higher on the Green building day and 101% higher on the Green+ building days than on the Conventional building day (p<0.0001). VOCs and CO2 were independently associated with cognitive scores.

Second, based on the finding of improved cognitive scores in buildings with enhanced ventilation, the productivity benefits were compared to the environmental and economic costs of doubling ventilation rates. The costs were less than $40 per person per year in all climate zones investigated, while the benefits in terms of productivity exceeded $6,500 per person per year. The environmental impacts could be mitigated through the implementation of energy recovery ventilators (ERVs).

Lastly, we conducted building assessments of 10 high-performing buildings (i.e. buildings surpassing the ASHRAE 62.1-2010 ventilation requirement and with low VOC concentrations) in 5 cities around the U.S. while tracking the health and productivity of office workers in those buildings. Even among high-performing buildings, workers in green certified buildings scored 26.4% higher on cognitive function tests than those in non-certified buildings. Sleep Quality scores were 6.4% higher in green certified buildings, suggesting an impact of the building on sleep quality.

We show significant benefits to cognitive function and health in green buildings through multiple experimental approaches, driven by factors consistent with the public health literature.