Graduated Designs: School glazings: a multifaceted opportunity
School construction is booming. Just two years ago, McGraw-Hill’s Dodge estimated 150 million square feet of space for kindergarten through 12th grade would be built in the United States compared to about 99 million square feet in 1990. Why is this one of commercial construction’s most active areas? According to a 2005 article in Architectural Record, the increase in school construction is attributed to more students, changing demographics and the aging of buildings constructed at least 50 years ago.
Today’s schools look and feel substantially different than those built in the 1950s. The American Institute of Architect’s Committee for Architecture in Education notes that new schools are being designed around green architecture and are likely to utilize natural materials in construction, large operable windows for natural light and cool air, and high-efficiency HVAC systems.
Support for “green” schools also is coming from the federal government. On Sept. 13, 2006, the Senate Environmental and Public Works Committee approved a bill that would authorize more than $200 million to promote environmental “friendly” schools and federal buildings.
Impact-resistant glazing keeps occupants safe
New building code regulations require glass in hurricane-prone areas of the country to be impact resistant. Often schools are designated as emergency shelters in these areas, so windows and doors must be impact resistant to keep building occupants safe in an extreme weather event.
Safety glazing on the inside of a school building is a requirement dating back to the 1970s. Today, schools and athletic facilities are required to have safety-glazing products that meet the Consumer Product Safety Commission standard 16 CFR 1201. Old wired glass that cannot meet the impact requirements of the CPSC standard should be replaced with a code-complying product. Areas most affected are doors, glazed panels adjacent to doors, glass partitions, and glass in gymnasiums.
Daylighting benefits student productivity
Increased daylighting in schools has been shown to result in improvements in student productivity. According to a 1999 study by Pacific Gas and Electric Co. of San Francisco on end-of-year test scores compiled by the Heschong Mahone Group of Oakland, Calif., students in classrooms with the most daylighting were found to have 7 percent to 18 percent higher scores than those in classrooms with the least daylighting. In San Juan Capistrano where the study was able to examine improvements between fall and spring test scores, students with the most daylighting progressed 20 percent faster on math tests and 26 percent faster on reading tests in one year.
In a 2003, Heschong Mahone Group completed a second series of studies on human performance on behalf of the California Energy Commission’s Public Interest Energy Research program. The PIER study compared the performance of more than 8,000 third- through sixth-grade students in 450 classrooms in the Fresno Unified School District. It found that the visual environment, including a pleasant view out of windows in a classroom, supports better performance outcomes.
While the study reinforced the importance of windows in a classroom, it also noted that glare and direct sun penetration into classrooms, especially through unshaded east- or south-facing windows, are associated with negative student performance. In addition, the study noted the importance of minimizing distracting noise in the classroom and providing ventilation and acceptable air quality.
Skylights and clerestories can bring in an abundance of light without creating unwanted glare. In addition, with natural light comes a decreased usage of electric lights during school hours. This might lead to a downsizing of HVAC equipment, a positive step in decreasing energy usage.
Noisy classrooms affect student performance
Overwhelming evidence suggests that U.S. classrooms are too noisy. Good acoustics are fundamental to good academic performance, says Mark Schneider, political science professor at State University of New York at Stony Brook.
“Students exposed to airport flight-path noise, for example, scored 20 percent lower than their cohorts,” Schneider says. “Evidence indicates also that high background noise causes stress and reduced performance for teachers as well as for students.”
To understand the performance issues around acoustics and schools, designers might want to work with an acoustical consultant or review ANSI S12.60-2002, Acoustical Performance Criteria, Design Requirements and Guidelines for Schools. Glazing options that improve acoustical performance of windows include laminated glass and insulating glass units.
Glazing provides security without bars
Some schools are being designed with large expanses of exterior glass to provide security to the building. While potential vandals can see into the school, it also means that those on the inside of the building will see them. This tends to thwart vandalism during daytime hours. If a burglar attempts to gain entry after hours, laminated glass, perimeter lighting and a reliable alarm system help to deter entry and further criminal activity. Windows designed to provide security, as opposed to metal bars over windows, create a much more appealing façade.
The Detroit Children’s Museum in Michigan, owned by the Detroit School District, features laminated glass in windows to provide protection from smash-and-grab criminals. The glass is an effective deterrent used in conjunction with security cameras and an alarm system. The laminated glass in the museum served as a prototype for other schools in the Detroit area, says Robert F. Moore Jr., senior deputy chief executive officer of Detroit Public Schools.
LEED provides design guidance
The Leadership in Energy and Environmental Design Green Building Rating System, administered by the U.S. Green Building Council of Washington, D.C., is a voluntary, consensus-based national standard for developing high-performance, sustainable buildings. The rating system is a self-assessing measurement tool divided into five environmental categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environmental quality.
Examples of LEED school projects that represent a growing number of environmentally friendly, energy-efficient schools being built in the United States include the Clackamas High School in Clackamas, Ore., and the Homewood Middle School in Birmingham. Clackamas was awarded LEED Silver certification and received points in the energy and atmosphere, and indoor environmental quality categories for incorporated passive solar, lighting controls, daylighting and daylight-harvesting strategies into the project.
Homewood is situated in a north-south direction to utilize winds and daylighting. Shading devices are used on the south side of the school and large windows are on the north side. A direct-digital-control system helps create daylit environments in 95 percent of the school.
Energy Star Schools program
While the LEED program offers a programmatic design approach, the Energy Star Schools program is specifically designed to cut energy usage in schools. The Department of Energy reports that the energy bill to run America’s primary and secondary schools is a staggering $6 billion.
To aid in the design of energy-efficient schools, DoE publishes its Energy Design Guidelines for High Performance Schools. This publication is part of the Rebuild America Program and is geared to seven different climates.
The Alexandria City Public School District in Virginia has been an Energy Star partner since 1992. The school district took steps to offset the increase in energy that resulted when air conditioning was installed in nine buildings. One of these steps was the installation of new windows with insulating glass.
High-performance windows are an important component in energy-efficient schools. “Today’s commercial windows offer features such as warm-edge spacers and thermal barrier systems that enable these products to surpass energy code requirements,” says Robin Randall, vice president of marketing at Traco, Cranberry Township, Pa.
Randall says windows going into schools are tested to Schaumburg, Ill.-based American Architectural Manufacturers Association standard 101-IS2 for air infiltration, water penetration and structural performance. Projects that require an “AW,” or Architectural Grade, rating also will undergo lifecycle testing to ensure long-term durability and performance. All in all, she says that school districts are likely to see quick paybacks on their investments in new windows.
Savings by Design is a program sponsored by four of California’s largest utilities under the auspices of the Public Utilities Commission that encourages high-performance nonresidential building design. The program offers assistance to make buildings more energy efficient and sponsors an annual design competition.
In 2005, an award of merit went to the Cesar Chavez Elementary School in Long Beach. This K-5 school set on 2.5 acres performed 29.3 percent better than California’s Title 24 energy requirements. A citation for classroom design went to the Solana Pacific Elementary School in San Diego, which was designed to take advantage of on-shore breezes for natural passive cooling and features clerestories to enhance natural lighting.
Designing the building envelope
Window design is a critical component of the design of school building facades. According to a recent article on high-performance school characteristics written by Charles Eley in the May 2006 issue of ASHRAE Journal, “High quality low-e windows should be used, but they should be positioned on the north or south sides of each classroom to reduce direct sun penetration and glare.” Eley, who works for Architectural Energy Corp. in San Francisco, notes that windows on the south side of a building should be shaded with overhangs and light shelves should be considered to increase daylighting penetration into the classroom.
In addition to traditional window and door systems, school projects can incorporate curtain walls and overhead glazing. “Many school systems are utilizing glass curtain wall and skylight systems to increase daylighting,” says Greg McKenna, product engineering manager, Kawneer Co., Norcross, Ga. “One recent Kawneer project, the Sky Vista Middle School in Aurora, Colo., incorporated both types of systems to bring natural light into the interior of the building.”
Future outlook for school design
The use of high-performance glass in vertical and overhead applications offers designers the opportunity to take advantage of natural light, thereby, reducing the use of electric lights in schools. This reduces energy consumption, and allows students and teachers to work in a pleasant learning environment. The key to using more glass is to understand building orientation, climate issues and the performance capabilities of the material itself. Manufacturers have a wealth of products available, from commercial windows and doors to skylight and curtain-wall systems.
71 Progress Ave., Cranberry Township, Pa. 16066, 800/837-7002,
Kawneer North America,
555 Guthridge Court, Norcross, Ga. 30092, 877/767-9107,
Architectural Energy Corp., 142 Minna St., San Francisco, Calif. 94105, 415/957-1977,
Heschong Mahone Group,
11626 Fair Oaks Blvd., Suite 302 Fair Oaks, Calif., 95628, 916/962-7001, www.h-m-g.com
Mark Schneider, State University of New York at Stony Brook;
His article “Do school facilities affect academic outcomes” can be found at www.edfacilities.org/pubs/outcomes.pdf