ROI: Healthier, more productive occupants
At the heart of our built environment—whether homes, offices, schools, or other building types—are the occupants. According to the U.S. Environmental Protection Agency (EPA), Americans spend 87% of their time inside buildings, making the built environment they inhabit critical.
Businesses, individuals, and society benefit from better working environments. Key health benefits include improved air quality, thermal comfort, and access to daylight. A study found that high-performance design elements that address these key benefits produced a total net value of $55.47/sf for increased productivity and $9.03/sf for improved health and wellness, through reduced absenteeism and missed work time, over 10 years (Attema 2018).
See AIA's Framework for Design Excellence: Design for Wellbeing.
Literature review completed by University of Washington’s Integrated Design Lab for AIA in 2020.
Indoor air quality (IAQ)
Good IAQ ensures that building occupants are healthy and productive, leading to benefits for individuals, business owners, and communities. Building parameters that affect IAQ include indoor and outdoor sources of pollution, ventilation rates, airflow patterns and pressure, and air filtration (Sujanoa 2019).
Key indoor air quality talking points:
- Bringing fresh air into a space dilutes indoor pollutants, prevents recirculation of contaminated air, and ensures required outdoor ventilation rates are met (Gerardi 2010).
- Building occupants generate pollutants and odors through their indoor activities, so it is important to regulate ventilation rates based on occupant density to ensure proper dilution of indoor pollutants (Kajtar 2011).
Improved IAQ improves occupant health:
- Indoor pollutants can cause morbidity in building occupants, but diluting these pollutants through increased ventilation can reduce their effects on occupants’ health (Mendell 2013, Allen 2016).
- A LEED Gold-certified office refurbishment that enhanced indoor ventilation for 150 employees saw an annual savings of $85,000 per year due to a 44% reduction in absenteeism because of better worker health (World GBC 2018).
Improved IAQ improves productivity:
- Reducing indoor air pollutants through increased ventilation has been shown to increase productivity (Seppanen 2006, Allen 2016).
- A study found that changes in CO2 concentrations from 550 to 945 ppm resulted in a 15% reduction in cognitive test scores. Changes in concentrations from 550 to 1400 ppm resulted in a 50% decrease in cognitive scores. Overall, the typical participant’s cognitive score across all nine cognitive function domains decreased by 21% with a 400 ppm increase in CO2 concentrations (Allen 2016).