Keep Indoor Air Fresh While Saving Energy
“Air is the No. 1 route of exposure to unhealthy substances in the indoor environment,” he said. “What’s healthy for people should not be neglected in favor of what’s healthy for the planet; rather, the two goals should peacefully coexist. Adequate fresh air should be an equal priority to energy savings. Controlled mechanical ventilation is the best way to achieve both intelligently.”
The most important thing for contractors to be doing now, to increase their IAQ work, is the most important thing many have been advising them to do for a long time: “Educate, educate, educate the consumer about the tradeoff that exists between tightened homes and indoor air quality, and offer solutions to address both,” said Rathey. “Contractors should learn to measure indoor air contaminant levels using handheld devices, then inform the consumer about available solutions which they can provide.”
NEW WHITE PAPER
HHI and the Home Ventilating Institute (HVI) jointly released a White Paper, “Victory over VOCs - Energy-Saving Fans and Other Devices Help Keep Indoor Air Fresh.” It explains that “IAQ has been a growing concern, particularly when it comes to newer, energy-efficient homes. While tight, well-insulated homes save money and are better for the environment, they may also trap unhealthy indoor pollutants inside.”
While energy-saving homes are good at keeping in heat or air conditioning, this may cause them to retain high levels of harmful compounds, the paper points out. The U.S. Environmental Protection Agency (EPA) estimates that concentrations of volatile organic compounds (VOCs) can be up to 10 times higher indoors than outdoors. (VOCs are carbon-based gases emitted into the air by common household products or furnishings.)
“A few of the more obvious sources are solvents, cleaning products, fuels, and cigarette or wood smoke,” said Rathey. In addition, flooring, upholstery, fabrics, paints/varnishes, and cabinetry can also emit VOCs. Other potential sources can include cosmetics, dry-cleaned clothing, hobby and craft supplies, newspapers, photocopiers/printers, moth balls, and air fresheners.
The severity of their health risks depends on factors such as which compounds are emitted (benzene, for example), concentration levels, and the length of the exposure time.
The paper points to source removal and adequate, year-round ventilation as solutions.
“Good ventilation is critical in order to dilute the concentration of VOCs indoors,” said Jacki Donner, CAE, executive director of the HVI. “Mechanical ventilation systems work year round in any kind of weather to remove the stale air inside the home and bring the fresh air from outside indoors.
“While older methods often required a tradeoff in terms of energy efficiency and weren’t practical in all weather conditions, modern technology … preserves energy efficiency while keeping indoor air fresh in all seasons.”
Ventilation products cited in the paper include:
• Exhaust fans with high-efficiency motors, which remove pollutants and moisture in specific areas of the home such as in bathrooms, showers, kitchens, and workshops and utility areas.
• Whole-house comfort ventilators; properly located, it draws cooler outside air through screened windows and doors, pulls it up through the house, and exhausts it, usually through static vents in the attic.
• Heat recovery ventilators (HRVs) and energy recovery ventilators (ERVs); for whole-house ventilation, HRVs and ERVs bring in outdoor air, circulate it through the home, and expel stale air to the outside while preserving energy. The heat from the exhaust air is retained by the unit’s core and used to warm the air coming in from the outside. In the summer, the process works in reverse. An ERV can also modulate the moisture that is retained or lost.
In addition to the white paper, the two organizations have produced a Q&A-format consumer e-book that provides information on how ventilation affects IAQ. The free publication may be accessed at www.jantrain.com.
For more information, visit www.healthyhouseinstitute.com and www.hvi.org.
Publication date: 01/24/2011