One in three homes in U.S. metropolitan areas have at least one problem such as water leaks, peeling paint, holes or rodents that could harm residents' health or safety.
Efforts to address all health risks posed by housing are increasing. Poor indoor air causes up to 40 percent of asthma, which has nearly tripled among children since 1980.
A recent study was the first to compare metro areas based on 20 health-related housing characteristics. Charlotte, Anaheim, and Atlanta were cities with high numbers of healthy homes. Oakland, San Francisco and New York City were among those ranked lowest. The most common problem was water leaks, which can cause mold that can trigger allergies and asthma.