Human beings spend the majority of their time indoors. European research indicates that the average person spends about 20 hours a day inside. Similarly, the average American spends nearly 90% of their time inside. Environmental factors play a key role in our health, and indoor environments are no different. Though the buildings surrounding us – whether at work or at home – can have a direct impact on our well-being, they are often overlooked when we think about creating a healthy lifestyle.
Thankfully, awareness around the impact of the built environment on human health is on the rise. There is much research being done about the correlation between building design and our well-being and productivity. The principles of healthy building design are growing in popularity, increasingly adopted by architects and contractors alike. Organizations like International WELL Building Institute and Fitwel exist to develop and document these standards, and even assess and certify buildings based on their level of healthy design.
So how exactly can building design influence our well-being? There is a growing body of research documenting the positive impacts of healthy building design, from reductions in illness and absenteeism to improved productivity and workplace satisfaction. Compelling trends are emerging all the time, but here are some key factors:
The Environmental Protection Agency (EPA) warns that the air we are exposed to at home or at work can be more polluted than the outdoor air in “even the largest and most industrialized cities”. Often, that is due to poor ventilation and off-gassing of toxic chemicals from common household products. In recent years, we have become more aware of the volatile organic compounds (VOCs) that may be found in paint. But carpets and furniture are also common culprits.
Beyond the obvious health implications, indoor air quality has also been shown to influence cognitive performance and work productivity. Researchers have found that doubling the ventilation capacity of an indoor space doubled their subjects’ cognitive function test scores. Another study found that doubling the outdoor air supply rate through increased ventilation could increase office work by about 1.5 percent, and reduce the prevalence of sick-leave by about 10%.
According to 9 Foundations of a Healthy Building (a program at the Harvard T.H. Chan School of Public Health), ventilation is important to help control or mitigate indoor sources of odors, chemicals, and carbon dioxide. That being said, the building design should avoid using outdoor air intakes near common sources of air pollution, like busy roads.
Indoor air should be filtered to remove harmful particles, and it’s important to select building materials with low chemical emissions. The goal is to limit occupants’ exposure to volatile or semi-volatile organic compounds (VOCs). Avoid using building materials known to contain legacy pollutants, defined as chemicals which remain in the environment long after introduction. Asbestos is a well-known example, but others include lead and polychlorinated biphenyls (PCBs).
Finally, limit vapor intrusion through the use of vapor barriers. Indoor environments should maintain humidity levels between 30% and 60%. One study even found that test subjects’ cognitive scores improved by 5.4 percent when buildings were kept within the optimal range of humidity.
Nature has been shown to have a profound effect on mental and emotional health. Exposure to nature is correlated with everything from reduced stress to increased happiness and creativity. One study found that viewing dynamic natural scenery triggers a physical response in our brains that is more pleasurable versus staring at a blank wall. As documented in the 2015 Human Spaces Report, employees who work in environments that incorporate natural elements report a 15% higher level of well-being.
Access to natural light can also impact our mental and physical wellness, as well as our productivity. A Harvard Business Review article references several relevant studies, which demonstrate that the absence of natural light can leave employees feeling tired and gloomy. Other research found that people exposed to daylight in the workplace report 63% fewer headaches and a 51% reduction in eye strain. Yet another study found that 70% of employees report improved work performance thanks to natural light. You don’t need to understand the interaction between lighting and circadian rhythms to appreciate these numbers.
Where possible, design spaces so that all work stations have direct lines of sight to exterior windows. Use windows and skylights to introduce as much daylight as possible, and supplement with blue-enriched lighting where necessary. Ensure task lighting is adequate to reduce eye strain.
Incorporate nature and natural elements to bring the outdoors inside. If outdoor views are visually unappealing, consider incorporating a green wall or living wall into your design. Thanks to the growing body of research supporting the connection between nature and human health, biophilic design is quickly gaining popularity. If you’re looking for resources about biophilia in building design, the Interface blog is a great place to start.
Active design is the practice of laying out a building or space in a way that encourages mobility and physical activity. This is important in building design due to the types of activities we normally perform indoors. At work, many of us spend up to 8 hours a day sitting at a desk. Meanwhile, at home, we are not much more encouraged to move. In many countries, including the United States and Canada, dwelling sizes are shrinking – meaning you likely don’t need to go very far to get whatever you might need.
The risks of a sedentary lifestyle are well-documented. One study found that sitting for excessively long periods of time is a risk factor for early death, even if you exercise regularly. Conversely, physical activity is linked to a number of health benefits, including lower blood pressure, improved sleep, and decreased stress.
In 2009, Volkswagen created a marketing stunt based on DDB Stockholm’s “Theory of Fun”. Volkswagen converted a staircase at a subway station into a set of working piano keys to encourage travelers to take the stairs instead of the escalator. As a result, the number of people who took the stairs instead of the escalator increased by 66%.
Though this was an awareness campaign for a motor company, it has implications for active building design. We are learning that by simply designing staircases that are more appealing, we can encourage more people to take the stairs.
The Center for Active Design developed a set of guidelines in 2010 to help architects and designers healthier urban spaces. The guidelines incorporate building design strategies that promote active living, for instance:
Of course, it is important to balance active design with provincial accessibility requirements to ensure that the building is navigable for people of varying physical abilities.
The above is just a basic list, but there are many other factors of building design that can have a direct impact on the wellness of the occupants. There are a number of informative resources on the subject of healthy building design, and the list grows every day. Below are some of the resources we found helpful in our research:
Healthy Buildings: https://forhealth.org/
HEAL Briefing | Healthy buildings, healthier people: https://www.env-health.org/wp-content/uploads/2018/05/Healthy-Buildings-Briefing.pdf
Interface Blog: https://blog.interface.com/
Center for Active Design: https://centerforactivedesign.org/guidelines/
International WELL Building Institute: https://www.wellcertified.com/
We’re here to answer any questions you may have.