​According to the U.S. Surgeon General, a healthy home "supports the health of its residents." By that definition many residences in California fail to meet that standard, according to a study by the California Department of Public Health and California Breathing. Homes can be plagued by structural problems — broken staircases or inadequate plumbing — but overlapping environmental issues that sicken occupants compound the problem.

The report used 2009 California Health Interview Survey (CHIS) data about tobacco-smoking habits to illustrate a common home health woe. While more than three-quarters of those surveyed prohibited smoking at home, smokers lit up every day in 3.3 percent of all homes, exposing their families and other building residents to secondary smoke and "third-hand smoke" — residual tobacco toxins that remain after a smoker has moved out. Other home health issues that caused respiratory distress were mice, cockroaches and mold. Health indicators as far-ranging as lead paint, home overcrowding, home affordability and neighborhood safety were also addressed in the study. CHIS data were to illustrate several of these categories. The report said it takes a team — including health advocates, policymakers and government agencies — to work with property managers and others to develop policies, such as banning smoking from large residential buildings, that help maintain health of houses and their residents.