Building Schools that Support Learning
By Tom Brooks-Pilling and Chris L. Wright September 2005 - Green
When the facility owner’s mission is to develop tomorrow’s leaders, goals for projects extend well beyond “on-time and under-budget delivery.” After all, educational facilities are more than simply buildings — they are environments that support a teacher’s efforts to tap student potential.
The high-performance school is designed to help students and teachers perform at their highest level by providing a learning environment that is healthy, safe, comfortable, environmentally sound, and cost-effective to build, operate and maintain.
A healthy, safe learning environment provides good indoor air quality (IAQ) to protect the health of children, teachers and staff and to reduce absenteeism. According to the Environmental Protection Agency, poor IAQ is associated with increased circulation of pollutants, carbon dioxide, mold growth and respiratory disease. Children are most vulnerable to the problems associated with poor IAQ, in particular, asthma, headaches, dizziness and decreased alertness. In fact, asthma affects 4.8 million school-aged children, and is associated with absenteeism — approximately 10 million school days a year. Facility executives can help address IAQ concerns with increased mechanical ventilation rates and use of operable windows.
Ventilation, Acoustics Matter
Thermal comfort is essential for students and teachers to concentrate. Yet many schools are operating with outdated, inefficient mechanical systems, which have been further compromised over decades by deferred maintenance and piecemeal facility renovations.
Good acoustical quality is also key to learning. Researchers have found that too much background noise and reverberation impede learning, even for children with normal hearing; a good acoustical environment is even more important for the 20 percent of children who have some hearing loss. Excessive background noise over time is also associated with stress. Poor acoustical quality, over time, is one factor in low achievement. Yet in many schools, the same outdated mechanical systems (often low-cost classroom units) that contribute to thermal discomfort also create background noise and vibrations. In fact, mechanical systems are the No. 1 cause of indoor noise pollution. In addition, older schools typically lack effective acoustical treatment of ceilings, walls and floors.
Access to natural light is increasingly seen as being important to learning. In fact, research suggest that performance can be enhanced by 20 percent or more in classrooms with optimal daylight, but many schools designed following the oil embargo of the 1970s reduced the amount of glazing to limit solar heat gain and reduce HVAC use.
Additionally, a high-performance learning environment serves as both a community resource and a three-dimensional textbook. As a community resource, for example, a well-designed school provides learning opportunities to the community through after-school access to quality classroom, arts, fitness and public assembly spaces. As a three-dimensional textbook, a well-designed school teaches the next generation about the value and practices of environmental stewardship.
In addition to enhancing the learning environment, high-performance schools are also designed to be environmentally sound and cost-effective to build, operate and maintain. Sustainable design principles favor environmental sensitivity to the building site, water conservation, use of renewable materials and materials with recycled content, and use of energy-efficient systems, including renewable energy sources.
Sustainability at Work
Environmental sensitivity to the site preserves natural habitats and recreational open space. This approach contrasts with the approach at many older, sprawling K-12 school campuses. Likewise, development is condensed to reduce the total impervious cover created on the site. Non-structural treatment methods, such as bioswales, are used to manage storm-water runoff.
Similarly, site and interior plumbing water conservation methods are used to help maintain stream flows and healthy aquatic habitats. At the same time, these methods reduce the energy and associated costs required to pump, heat and treat potable water as well as the cost of waste supply and wastewater treatment. Approaches include use of on-site ponds or stormwater-detention basins for landscape irrigation.
Energy efficiency reduces pollution, slows global warming and decreases dependence on foreign oil markets while reducing operating costs. Sustainable approaches to enhance energy efficiency include high-performance glazing, high perimeter U values and replacement of inefficient equipment.
Sustainable design also takes advantage of the many durable, nontoxic building materials available. Today’s products contain a significant amount of recycled content, including steel, concrete and gypsum board. Similarly, using certified wood products produced from forests managed on a renewable 10-year harvest cycle, as well as the use of local and regional materials, helps preserve natural areas and slow resource depletion.
Application of sustainable design principles also creates savings — a hallmark of the high-performance school. For example, research shows daylighting can cut electric power consumption by 35 to 50 percent. Daylighting spaces using appropriate window glazing also creates less heat gain than artificial lighting, reducing cooling loads. Natural ventilation, including operable windows, can decrease cooling loads, yielding 10 to 20 percent savings in energy use. Similarly, energy-efficient building envelopes decrease heating loads. Water savings through water-conserving bathroom fixtures and landscaping strategies can reduce consumption by 30 percent.
When savings from decreased energy consumption are calculated, a high-performance school has the potential to lower overall operating costs considerably. Many owners focus almost exclusively on capital costs when considering system selection; however, they are learning to take a longer view. According to the General Services Administration, first costs represent 10 percent of total life cycle facility costs, while operational costs account for 90 percent of the total facility costs.
Passing the Test
Missouri’s Hazelwood School District is upgrading its school facilities to reflect current thinking about the best environment for learning. The second-largest school district in the St. Louis metropolitan area, Hazelwood School District covers 78 square miles. The district comprises three high schools, three middle schools, 20 elementary schools and three early childhood centers.
With more than 19,250 students, enrollment has grown faster than new schools can be built. And with 2,000 new homes in the planning phase, the district anticipates continued enrollment growth. As a result, the district’s high schools and middle schools are overcrowded. The middle schools are feeling especially squeezed, with 22 classrooms located in portable units.
With these issues in mind, the school district embarked on an ambitious capital plan in 2002 involving a new facilities master plan, a new elementary school, expansion and renovation of its two high schools, and four new middle schools.
One goal was to add classroom capacity and redesign the windowless, warehouse-like Hazelwood East High School. The existing school had been designed to facilitate the outmoded 1970s concept of the open classroom. Teachers coped as best they could by creating walls using screens, bookshelves and the like, but they could not effectively overcome the noise and distractions. Moreover, these efforts further taxed an inefficient mechanical system, contributing to the uncomfortable environment.
Building Better Space
The district’s goals for the $15 million project were better functional space, new space allocation and energy savings. The program provides new instructional space for core classes of this 2,000-student high school— math, science, social studies and communication skills — and renovates the classroom wing from an open classroom design to closed classrooms. The program provides clear opportunities to improve energy efficiency and use design to support student and teacher performance. The solution creates a science and math classroom addition and renovates existing classrooms using phased implementation to allow continual operation during construction.
Hazelwood East meets design criteria for health and safety, thermal comfort, acoustical quality, and optimization of natural and artificial light. IAQ measures include appropriate placement of air intake and exhaust, indoor pollutant source control, a construction IAQ management plan, and carbon dioxide monitoring. Designers specified low-VOC paints and coatings, carpet, composite wood, sealants and adhesives. Operable windows were punched into the formerly windowless building.
The renovation partitions the open classroom space into traditional closed classrooms, ensuring acoustical quality through use of acoustical ceiling, wall and floor treatments. In addition, the remote ground-floor mechanical equipment room eliminates noise and vibration from the HVAC system — a new gas-fired variable air volume hydronic re-heat system, which replaced the existing electric re-heat system.
Holding Energy Use in Check
The daylighting strategy includes effective siting of the new science and math wing, reorganization of the existing instructional wing to position classrooms along the exterior wall, addition of operable windows in all classrooms and skylights in corridors, and additional access to outside views. The new science and math building is sited to capture optimal daylight for both the new wing and the existing instructional wing without raising energy consumption.
The project uses the site’s topography and a compact building plan to reduce site disturbance and conserve water. Captured rain water is used to irrigate the low-maintenance landscape. For example, the new courtyard formed by the addition of the science and math wing functions as an outdoor classroom with native plants irrigated from a nearby pond. Impermeable surfaces are reduced through measures such as eliminating additional parking and use of a permeable surface for the fire lane. Indoor water conservation strategies include self-flushing and low-water-use plumbing fixtures.
The renovation and new classroom wing optimize energy performance using high-performance glazing, high perimeter U values and replacement of inefficient equipment. Building commissioning and continuous equipment metering systems are employed to measure and verify system efficiency.
The project uses renewable materials, such as certified wood products, and materials high in recycled content: concrete, carpet, sheathing, mineral wool insulation, vapor retardant, roof walkway pads, gypsum, board, ceramic tile and acoustical ceiling panels.
The school district used a Department of Natural Resources low-interest loan to purchase energy-saving systems. Life-cycle cost analyses show a payback on these capital investments of less than 14 years. Moreover, total project costs are projected at 10 percent less than budget.
The new math and science wing was completed for the 2004-05 school year. The interior renovation has been divided in three phases, and was completed in August. Effective construction scheduling and good communication between the school district and project team ensured the safety of building occupants and visitors and minimized disruptions to the school program.
School districts across the country are being held to higher standards, and the demand for accountability is stronger than ever. Educational facilities can become part of the formula that helps schools meet these tough standards. Indeed, the high-performance school facilitates learning by design — supporting students and teachers to perform at their highest level, all while conserving natural resources and delivering savings.
Tom Brooks-Pilling is director of architecture for the St. Louis office of Parsons Brinckerhoff. Chris L. Wright is superintendent of Hazelwood School District, St. Louis. Research supporting high-performance school design principles was compiled by Jeffery A. Lackney, assistant professor in the college of engineering at the University of Wisconsin-Madison.