Sustainability, the next wave

Making built environments healthier must be about more than numbers.


Remember sick building syndrome? Sick building syndrome originated as a result of the oil embargoes that began in the mid-1970s. In order to conserve energy during the Energy Crisis, buildings were built “tight” – with windows that couldn’t open, for instance. As an energy conserving measure, the air ventilation requirement was lowered from 15cfm per person down to 5cfm per person. An unexpected consequence: mold became trapped indoors along with chemicals released from cleaning products, ozone from photocopiers, pesticides sprayed by the exterminator, fumes from new carpets and paints and secondhand cigarette smoke drifting indoors from the ventilation system. We tried to save energy and got sick buildings.

Sick building syndrome was resolved through numbers, science and engineering mostly. The US increased air change rates to 20cfm per person, regulated VOCs in certain indoor applications, incorporated higher filtration media and so on. Sick building syndrome may seem like ancient history, but largely we still abide by its lessons. We assume that if we get the numbers right, we will get a healthy outcome.

But today, sustainability must be about more than that. We need to do a deeper dive into what creates healthy, productive indoor environments.


Forest Bathing in Japan

Let’s start with one thing we know, humans benefit from being outdoors. The popular Asian pastime of ‘forest bathing’ (not unlike hiking) has been researched extensively. It does not require heavy physical exercise, but rather is about enjoying the forest through the five senses: listening to the murmuring of a stream, birds singing, seeing the green color of the flora, smelling the fragrance of the forest, eating foods from the forest and just touching the trees. Instinctively, we suspect that getting out into nature has health benefits. In fact, research shows that just looking at a natural scene activates parts of the brain associated with balance and happiness. In a study at South Korea’s Chonnam National University, fMRI scans showed that when subjects saw images of mountains, forests, and other landscapes, they experienced heightened activity in the anterior cingulate gyrus (an area linked to positive outlook and emotional stability) and the basal ganglia (an area that’s been tied to the recollection of happy memories). The Japanese believe that forest bathing (shinrin-yoku in Japanese) does wonderful things for the body. But now researchers at Tokyo’s Nippon Medical School have quantifiable evidence: In one study, women who spent two to four hours in the woods on two consecutive days experienced a nearly 50 percent increase in the activity of cancer-fighting white blood cells.


Roosevelt University dorms at the Wabash Building offer views of Lake Michigan.

We’ve come a long way since the days of sealed up, recirculating buildings outfitted with unhealthy materials. This is important as on average Americans spend about 90% or more of their time indoors. The good news is that recent research shows that exposure to nature, even from inside, has health benefits to us as well. While there has been significant research around the importance of indoor daylight for human health and performance, there is also an emerging consensus that access to a view of nature is significant. According to work of Roger Ulrich (1984), Mendell (1991), and Kellert (2005), seated views of nature and proximity to windows can be linked to reduced length of stay after surgery, reduced sick building syndrome, increased performance at a task, and overall improved emotional health. In addition to views, well-designed and properly located windows provide the benefits of daylight. Research is revealing that the natural variability of daylight over the course of the day, especially morning daylight, reduces length of stay for patients recovering from surgery, improves worker productivity and improves natural melatonin production (helping us sleep at night among other things).


Maximizing daylighting at XL Group Chicago offices

Interestingly, humans receive some benefits even from a simulation of natural daylight. According to research at the Lighting Research Center at Renselaer Polytechnic Institute there is a relationship between exposure to ultraviolet lighting and melatonin production. Melatonin controls circadian rhythms, sleep cycles and affects performance at tasks and cancer cell development (Bullough et al 2006). An experiment on 20 night shift workers revealed the importance of time of day light intensities to performance at tasks. The workers showed statistical improvement in short-term memory and grammatical reasoning tasks when lit under large skylight fixtures with hidden fluorescent lamps. By steadily decreasing that illumination, simulating natural daylight from midday to dusk, night worker performance improved.

The health improving value of high outside air delivery rates also shows up in recent research, often the result of increasing ventilation rates. However, it is not clear if increased levels of outside air are more effective when delivered through operable windows or by mechanical means. Studying countries where natural ventilation is commonplace yields some answers. A 1990 study of 43 buildings in the UK compared naturally ventilated buildings to mechanically ventilated ones. There was a 9% reduction in sickness and absence and a 59% reduction in self-reported sick building syndrome symptoms among workers in natural ventilated spaces as compared to workers in air conditioned buildings (Robertson link). However, natural ventilation has its limits, especially when it comes to overall thermal comfort. Opening the windows, importantly, has more benefits than just allowing air to flow.


Views of the outdoors at University of New Mexico Cancer Center promote healing.

If all of the above does a human good, what about actually bringing nature into our spaces? Can a fern in the cubicle have the same effect as looking out the window onto a park? A 1998 experiment (Fjeld), showed that even potted plants benefit building occupants. Researchers investigated the impact of potted plants on self-assessed health symptoms of 51 employees. When a substantial number of plants were present in their offices, there was on average a 21% reduction in reported sick building syndrome symptoms among occupants.

Reducing toxins in our indoor environments and advocating transparency in the market place is a hot topic in our industry these days. An emphasis on minimizing VOCs has grown into an interest in reducing toxins in our indoor environments in general. With the Red List, Health Declaration Collaborative, and the Pharos Project, we’re taking this awareness of toxins to a new level. If a building can’t avoid Red List containing products completely, there are specific leafy indoor flora species that can scrub the air clean. Plants can moisturize indoor air and cleanse it of toxins. NASA has studied indoor plant cultivation for years, with an eye toward future sustainable colonies in space. The agency’s researchers discovered that some plants absorb benzene and formaldehyde and reduce the numbers of airborne bacteria and mold spores by half. For a maximum benefit, 15 to 18 houseplants in six-to-eight inch containers will naturally cleanse the air in an 1,800 square-foot space.

Why does connecting ourselves with nature even in an indoor environment work? One theory: As a species we evolved spending more time in nature than not. Researchers say human beings (homo sapiens) emerged around 300,000 years ago but the first cave paintings date from only 30,000 years ago and it has only been 12,000 years since we started farming and settling down. Up until then, we were hunter gatherers. This represents 288,000 years of living and surviving in nature. “Humans are evolved organisms and the environment is our habitat,” says Frances Kuo, a professor of natural resources and environmental science and psychology at the University of Illinois.

This is why we still respond to nature even as our modern lives become more technology based and our living environment continues to be primarily indoors. Our 288,000 year old DNA still responds to natural stimuli.

And yet sustainability has largely become about materials lists, engineering to reduce cooling/heating and water use loads, and the like. These are valid, relevant and easily understood benchmarks, but are not enough. We can make our built environments even healthier. In formulating sustainability’s next step, we need to be conscious of all of the ways in which human health benefits from a connection to the outdoors. As designers, the onus is on us to make the indoor environment a healthier place, and largely that means bringing the outdoors in.

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