High-performance schools are facilities that improve the learning environment while saving energy, resources and money. Creating a high-performance school requires an integrated design approach. Key systems — including lighting, HVAC, electrical and plumbing — must be considered from the beginning of the design process.
The Sustainable Buildings Industry Council (SBIC) says that school districts using sustainable, high-performance design and construction concepts can cut utility costs — 30 to 40 percent each year in new schools and 20 to 30 percent in renovated schools.
“High-performance schools can provide remarkable benefits, including increased attendance, healthier indoor air quality, reduced operating costs, reduced liability, and reduced environmental impact,” says William H. Sanders III, acting director of the U.S. Environmental Protection Agency (EPA) Office of Children's Health Protection. “By adopting green building strategies, we can contribute substantially to the academic achievement of our students, as well as to the economic and environmental performance of our nation's schools.”
One way to create such an environment in schools is through effective ventilation and moisture control.
Most people are aware that outdoor air pollution can damage their health, but many do not know that indoor air pollution also can have harmful effects.
According to the EPA, more than 53 million children and 6 million adults spend a significant portion of their days inside school buildings. The EPA also says that exposure to mold is believed to be linked to health problems, including allergic reactions or even asthma attacks.
In a classroom of 30 children, about three are likely to have asthma. According to the U.S. Centers for Disease Control and Prevention, asthma causes U.S. students to miss 14 million school days per year. Some of those missed days are likely attributable to poor indoor air quality.
A classroom's indoor environment plays a sizable role in a student's ability to concentrate and learn. Failure to prevent indoor air problems can:
Increase the potential for long- and short-term health problems for students and teachers.
Detract from the learning environment, occupant comfort, and attendance.
Reduce teacher and staff effectiveness.
Accelerate the deterioration of school facilities and equipment.
Increase the potential that schools will have to be closed, or occupants temporarily relocated.
“Poor indoor air quality remains one of the top health concerns that our members face,” says Jerry Newberry, director of the National Education Association's Health Information Network. “As teachers and education professionals, we are concerned about our students, because we know that our working conditions are the students' learning conditions, and we believe a healthy learning environment is integral to providing quality education.”
A number of factors contribute to poor indoor air quality in schools: construction of more tightly sealed buildings; reduced ventilation rates to save energy; the use of synthetic building materials and furnishings, pesticides and cleaning supplies; and limited maintenance budgets. In addition, activities and decisions such as deferring maintenance can lead to moisture and ventilation problems.
Many U.S. schools are overcrowded and in disrepair, often with substandard plumbing and inadequate HVAC systems. In the American Society of Civil Engineers' latest assessment of the nation's infrastructure, U.S. schools received a “D.” Creating a comfortable, high-performance environment can help students improve their academic performance. Controlling moisture and providing adequate ventilation can help create such an environment.
Schools present unique dehumidification challenges because their ventilation requirements differ from other types of buildings. The amount of outdoor air required in a room is based on the number of people that will occupy that room. A typical 1,000-square-foot classroom will be occupied by 30 people and require a high ventilation rate and, at certain times of the year, a high dehumidification capability. Managing moisture also is important when buildings are empty and in regions that experience hot, humid weather.
Schools can reduce energy consumption and save money while improving indoor air quality through the use of energy-efficient dehumidification controls, such as hot gas reheat. Maintaining a constant level of humidity through the use of dehumidification products saves energy and extends the life of an HVAC system. Hot gas reheat systems can lower building life-cycle costs and provide premium indoor air quality in any climate. Some manufacturers' hot gas reheat systems comply with the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) 90.1 guidelines that limit the amount of new energy allowable for dehumidification using reheat.
It is not necessary to eliminate all moisture in the indoor environment; facility managers can control moisture through proper management. Selecting the right HVAC system allows school facility managers to maintain effective dehumidification, reduce energy consumption and improve the indoor environment. Schools should partner with an HVAC provider that offers dehumidification solutions for the education industry, including preventive maintenance of the building envelope, where deterioration or damage can allow moisture into the building.
To ensure proper moisture management in school buildings, facility managers should consider the following maintenance tips:
Fix leaky plumbing and leaks in the building envelope as soon as possible.
Clean and dry any wet or damp spots within 48 hours.
Identify and eliminate the sources of excessive moisture immediately before mold problems can occur.
Increase the surface temperature and reduce humidity to prevent moisture due to condensation.
Insulate or increase the circulation of air to increase surface temperature.
Increase ventilation (if outside air is cold and dry), or dehumidify (if outdoor air is warm and humid) to maintain low indoor humidity (below 60 percent relative humidity).
Keep HVAC drip pans clean, flowing properly, and unobstructed.
Perform regularly scheduled building inspections and HVAC maintenance.
Bringing existing K-12 public schools to proper standards will cost billions of dollars. New facilities will cost billions more. Effective moisture management will help schools get the most out of those huge investments.
A properly designed and maintained HVAC system is one of many factors to consider when seeking indoor air quality improvements. Properly maintained, energy efficient dehumidification systems can reduce energy costs and diminish the likelihood of damage caused by excessive moisture.
Johnson, Institutional Markets Director for Trane, has worked in the building systems, services and energy markets for more than 18 years. He serves on the U.S. Department of Energy's Energy 2005 Planning Team.
Number of students likely to have asthma in a classroom of 30.
Source: U.S. Centers for Disease Control and Prevention.
30 to 40
Percentage of utility costs that new schools can save each year by applying sustainable, high-performance design and construction concepts.
Source: Sustainable Buildings Industry Council.
20 to 30
Percentage of utility costs that renovated schools can save each year by applying sustainable, high-performance design and construction concepts.
Source: Sustainable Buildings Industry Council.