Case Study - Daylighting on Human Performance
Introduction
This report looks at the effects and benefits of daylighting on human performance, with a special focus on the added benefits of using skylights to augment natural light levels in academic settings. This report goes beyond the traditional benefits (view and ventilation) associated with daylighting from windows to explore the value of more natural daylight from all sources. Overall, there is a compelling connection between daylighting and student performance.
The Benefits of Daylighting
The value of daylighting is hard to dispute when you ask people what they like, and it's true for nearly all environments, from the family room to the best office space. This should come as no surprise, since humans have lived in concert with the sky for thousands of years. Beyond our natural affinity for daylight, studies have proven that daylighting exerts a profound effect on a person's mood. Scientists believe that the changing intensity and duration of sunlight can affect our internal biochemistry. The best example of this is seasonal affective disorder, a "seasonal pattern" of unipolar and bipolar mood disorders. Exposure to daylight is known to increase the production of Vitamin D. The high illumination levels associated with daylight have become recognized as a treatment for seasonal affective disorder.
On the other hand, there are things people don't like about daylighting, and skylights in general. For instance, poorly designed skylights can be uncomfortable to be under. They're sometimes hot, and the glare can be too intense. Choosing the right daylighting system for the application can eliminate all of these problems. We'll talk more about these problems later in the study.
Daylighting in Schools
Growing evidence shows that natural daylighting can have a large impact on student performance. A study done by Heschong Mahone Group, "Daylighting in Schools," investigated daylighting and human performance. The study was done with three separate school districts, with differing climates, building designs, teaching styles, and curricula. We'll discuss a few of their findings relating to natural daylighting and student performance below.
Today, educators know that the superior quality of natural light improves both test scores and long-term retention. Skylights in particular have a profound effect on student performance. Well-designed daylighting has significant economic payoffs such as reduced demand for electricity (most rooms with skylights just need task lighting, rather than general lighting). But in the academic context, the real benefits are human: Clearly visible writing and work surfaces, better student health and general mood, better behavior, and improved arousal levels. The study indicated "most teachers felt that windows and daylight[ing] improved the mood of their students, keeping them calm and improving their attention spans. Higher illumination levels in daylit classrooms simply help to keep children more alert and capable of absorbing new information." 1 The phrase "walk on the sunny side of the street" captures common wisdom that people tend to have a more positive outlook under sunny conditions.
As well as all the other attributes related to daylighting and students, the study found that "students in daylit classrooms progress more quickly, gaining one to two points more over the course of the school year than students advancing at the average rate. By advancing more quickly, students in daylit classrooms could save up to one month of instruction time in the reading and math curriculum that could be used for other areas of learning." 2
For all other influences, students with the most daylighting in their classrooms progressed 20% faster on math tests and 26% faster on reading tests in one year than those with the least amount of daylighting. Students with well-designed skylights in their classrooms, ones that diffuse the daylight throughout the room, also improved 19-20% faster than those without a skylight.
As stated before, every school has different curricula and teaching styles, different school building designs, and very different climates. Yet there are consistently positive and highly significant effects. That consistency supports the proposition that there is a valid and predictable effect of daylighting on student performance.
Case Study - Blue Cap School
Blue Cap School took advantage of the benefits of natural daylighting by putting Major Industries' Guardian 275® translucent FRP skylight above the recreation area of the school. The skylight difuses natural daylighting throughout the recreation area, which improves the students' mood, alertness, and energy. This skylight also highlights the most desirable design traits of the building. The cedar beams, plaster walls, and skylight all complement each other to give this room an interesting look. This skylight is a 7'x 48' ridge made of translucent FRP which uses state-of-the-art surface protection to provide long-term protection against UV damage and fiberbloom.
Case Study - North Elementary School
North Elementary School used Major Industries' Guardian 275® Translucent FRP skylight to create a canopy that invites people inside. The canopy extends into the interior entryway of the building, allowing in natural daylight. This is a classic example of how you can use a skylight as a "pass-through" skylight. Tower, Pinkster, Titus Associates chose the 46' ridge skylight for the distinctive grid pattern that acted as a design element for the entrance of the building. The dual-purpose nature of this skylight (as a design element and a source of glare-free lighting) offers a "natural" welcome to each person as they pass through the entrance.
Case Study - Foster High School
This rather complicated design serves as a focal point for the central gathering area at the school. Major Industries designed the 36' x 36' Guardian 275® skylight to let in glare-free natural daylight. Translucent skylights provide beautiful natural daylighting, while reducing glare and heat loss. Their natural energy efficiency saves money and stabilizes HVAC loads. The internal lighting that this skylight produces has a profound effect on the school's mood and user satisfaction with its intended purpose. This skylight provides all the positive aspects of natural daylight without the penalties of direct sunlight. Foster High School also incorporated two other skylights into the building's design.
Historical Prejudices
The most common misconception about daylighting (and skylights in particular) is that they leak. And to be frank, poorly designed systems do. That's why it's important to understand the features to look for when choosing a system.
Today's best daylighting systems stress water management. In the final analysis, a skylight is a hole in a building's roof. We all know that structures settle, and building materials age. Just as siding and shingles need to be maintained, so do skylights. A poorly designed system exacerbates the inevitable changes that a building undergoes with age. The best daylighting solutions use compound gasketing systems (for instance, butyl exterior and EPDM or neoprene interior) and integral gutters. These design features, working together, stop most water infiltration. For the water that does get through, a system with integral gutters redirects it to the building exterior. In most cases, the owner won't even know that there was water infiltration.
Another prejudice that you must address is heat. Most often, this is the result of a poorly chosen daylighting system. In the U.S., choosing a glass-glazed daylighting system for a southern exposure can result in a space that's uncomfortable if people spend considerable time beneath it, without thermal mitigation through blinds, shading, or biological screening. When most people think of daylighting, they think of glass. However, there are several competing technologies, including twinwall polycarbonate and translucent FRP panels that provide most of the benefits of glass, while minimizing solar gain.
The Bottom Line
Skylights are a highly technical product, customized not only for the building's physical characteristics, but also for its geography, climate, and the application for the space. Choosing such a product requires an understanding of the basic technology, industry issues, and product limitations. Take the time to learn the benefits, and you'll be satisfied with the daylighting system that you chose.
Sources:
- Daylighting in Schools. Condensed Report, Heschong Mahone Group
- Daylighting in Schools, August 20, 1999
Students benefit greatly from access to natural light - visit our LEED for Schools page for more information on the USGBC's LEED for Schools Green Building Rating System™ and how Major's daylighting solutions may apply.
More Design Options
To see how Major Industries' daylighting products can add numerous benefits to your next project, check out our downloadable Daylighting Design Guides. From sales floors to classrooms, Major Industries has your daylighting needs covered.