posted by David Epstein, AIA, LEED AP on August 27, 2009
Recently, my colleague Steve Kredell and I attended the School Building Expo in Pittsburgh, PA. Many of the sessions focused on creating sustainable schools. Of particular interest to us was the keynote speech given by Vivian Loftness, FAIA of Carnegie Mellon University on the impact of green schools on health and learning. She was part of a team of researchers at the National Academy of Science who reviewed the scientific literature related to this subject and reported their findings, which are summarized below.
Quantifying the benefits of green building typically focuses on life-cycle costs. This approach looks at the cost of materials, the energy or resources they consume, and the cost and timing of maintenance and replacement. While many green building rating systems, such as LEED and CHPS, suggest improved student performance is a benefit, it has always been difficult to point to hard evidence in support of that claim. The notable exception (that we are aware of) being the “Daylighting in Schools” study by Heschong Mahone Group, 1999, which demonstrated increased student performance in day-lit schools.
So we were eager to hear the findings, as health and learning is of critical importance in an educational environment, and making the case for green schools, at least partly based on this criteria, while sensible, has not always been substantiated by readily available data.
The results of the study are documented in “Green Schools: Attributes for Health and Learning” by the Committee to Review and Assess the Health and Productivity Benefits, National Research Council, 2007. Below is the summary of their findings:
“After evaluating the research literature, the committee concluded that a green school with the following attributes would support student and teacher health, learning, and productivity:
So we were eager to hear the findings, as health and learning is of critical importance in an educational environment, and making the case for green schools, at least partly based on this criteria, while sensible, has not always been substantiated by readily available data.
The results of the study are documented in “Green Schools: Attributes for Health and Learning” by the Committee to Review and Assess the Health and Productivity Benefits, National Research Council, 2007. Below is the summary of their findings:
“After evaluating the research literature, the committee concluded that a green school with the following attributes would support student and teacher health, learning, and productivity:
- Dryness: Excessive moisture, which has been associated with adverse health effects, particularly asthma and respiratory diseases, is not present.
- Good indoor air quality and thermal comfort: Ventilation rates, air pollutants, humidity levels, and temperature ranges, which have been linked to human health, learning, and productivity, are effectively controlled.
- Quietness: The acoustical quality, which has been shown to affect student learning and the development of language skills, meets the newly released Standard 12.60, “Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools,” of the American National Standards Institute.
- Well-maintained systems: Building systems are commissioned to ensure that they perform as intended, and their performance is monitored over time. Routine preventive maintenance is implemented throughout a school’s service life.
- Cleanliness: Surfaces are disinfected to interrupt the transmission of infectious diseases, and measures are implemented to help control indoor pollutants that have been associated with asthma and other respiratory diseases.”
Within the report are more detailed findings and recommendations, with discussion. In some cases, there simply was not enough evidence to support a finding. In other cases, it was not possible to associate a cause with an effect. Ironically, the committee was not able to include daylighting as a benefit to health and learning. According to the study, the available literature did not adequately differentiate between artificial, natural light and corrective eyesight issues. The evidence of non-visual benefits of daylighting through the circadian system was noted, but also did not meet the “sufficiency of data” threshold.
In regard to the complexity of their task, the committee rightly notes that a building is a “system of systems” and that the focus of green school guidelines should emphasize these interrelationships, so that health and learning benefits are maximized along with energy and resource efficiency.