Barriers to improved ventilation in production housing

In addressing the goals of energy-efficiency and indoor air quality (IAQ) in homes, industry teams in the U.S. Department of Energy's Building America program are installing mechanical ventilation systems in tight homes. A variety of designs - some simple and inexpensive, some more sophisticated - have been demonstrated. The advanced designs provide more consistent ventilation over time, more uniform ventilation among rooms, and source control measures that reduce the air-change requirement. However, most homebuyers are not fully aware of IAQ issues and whole-house ventilation requirements, and are thus not willing to pay the incremental cost of improved systems. Because the applicable standards do not require these improvements, lower-performance systems are often installed despite the best intentions of the engineering teams. This paper describes the ventilation approaches used by the teams, shows test results that illustrate performance issues, and discusses obstacles that hinder more widespread application of improved systems.