State of Healthy Housing:  Frequently Asked Questions

The following list of questions and answers are intended to highlight the background and results of our 2019 State of Healthy Housing report.

Which MSAs (metropolitan statistical areas) have the most healthy and least healthy housing conditions?

  • Best MSAs: Based on the scoring, the metro areas of Seattle, WA; Jacksonville, FL; San Jose, CA; Miami, FL; Orlando, FL; and Washington, DC, have the healthiest housing conditions.
  • Worst MSAs: Based on the scoring, the metro areas of San Antonio, TX; Oklahoma City, OK; Tucson, AZ; and New York, NY, have the least healthiest housing conditions.

Which central cities have the most healthy and least healthy housing conditions?

  • Best central cities: Based on the scoring, Raleigh, NC; Jacksonville, FL; Portland, OR; and San Jose, CA, have the healthiest housing conditions.
  • Worst central cities: Based on the scoring, San Antonio, TX; New York, NY; Houston, TX; and Baltimore, MD, have the least healthy housing conditions.

How were the data for the study collected?
The study uses data from the American Housing Survey (AHS), which is conducted by the U.S. Census Bureau for the U.S. Department of Housing and Urban Development (HUD). The results and details are available at

The AHS collects the following data:

  • Individual household characteristics
  • Owner/renter’s income
  • Housing and neighborhood quality
  • Housing costs
  • Equipment and fuels
  • Size of housing unit
  • Recent moves.

National data are collected in odd-numbered years, and data for a subset of the nation’s metropolitan areas are collected approximately every two years. The years of the metro surveys included in this report are 2011, 2013, and 2015. The survey includes apartments, single-family homes, mobile homes, and vacant homes; however, data were limited to occupied dwellings for this report.

Until 2015, the AHS returned to the same housing units to gather data, while regularly adding units to represent new construction. The 2015 AHS underwent a major redesign with a new pool of homes surveyed for the first time since 1985. HUD has also revised its strategy for selecting metro areas over the years. The current strategy is to survey the 15 largest metro areas and a sample of 10 other large metro areas every other year. The strategy began in 2015 and continued with the 2017 sample.

Why isn’t my city listed?
The U.S. Census Bureau produces a Metro Edition of the American Housing Survey for a subset of the nation’s larger metropolitan statistical areas (MSAs), which are the same metro areas we cover in our rankings. All 53 metro areas in our rankings were sampled in 2011 or more recently.

Why aren’t serious problems (such as cockroaches, missing/inoperable smoke alarms, scalding hot water, and other housing problems) ranked?
The AHS does not have questions for every housing hazard, but we used as much of the data collected as we could. An overarching goal of the State of Healthy Housing is to increase interest and understanding of housing-related health hazards and to increase the size and scope of the American Housing Survey, the source of data for the study. We are advocating for increased funding for AHS to (1) include additional health-related questions in the survey, (2) ensure that the surveys are conducted according to the schedule set by HUD, and (3) to ensure that sufficient data are collected from each jurisdiction to enable rigorous analysis. In recent years, signs of cockroaches and presence of mold have been added to the standard questionnaire. Signs of roaches has been added to this year’s State of Healthy Housing report, while mold will be added in the future, when all years covered by the report include data on mold.

How are the “Basic Housing” rankings calculated?
To assess basic housing quality, NCHH ranks each community by the percentage of homes with severe or moderate housing problems. If the percentage of severe or moderate housing problems for a community is statistically significantly different than the concurrent national percentage, the community is designated as Most Healthy or Most Unhealthy.

How are the “Healthy Housing” rankings calculated?
The Healthy Housing rankings were developed using a composite score of the 20 healthy housing characteristics. For every community, the 20 housing characteristics are assigned a value of -1 (significantly better than concurrent national average), 0 (not significantly different from the national average), or 1 (significantly worse than the national average). The values are totaled to create a healthy housing score for each community (-20 being best and 20 worst). The communities are ranked based on their scores. A score of 0 is considered average.

We classified the communities as follows:

  • Score of -6 or higher: MOST HEALTHY
  • Score between -5 and -5: AVERAGE
  • Score of 6 or lower: MOST UNHEALTHY

How did you decide which housing characteristics to analyze?
We selected housing characteristics from the U.S. Census Bureau’s American Housing Survey that either directly or indirectly impact health or safety. The characteristics are largely based on the federal “housing quality standards,” which set forth the requirements for decent, safe, and sanitary conditions in federally owned or assisted housing. The AHS has been collecting information on these variables for over 30 years using a validated survey protocol. Based on expert opinion and, in some cases, documented research, all of the characteristics selected can be expected to affect the health of the residents adversely.

Are some housing characteristics weighted more heavily than others in the analysis?
No. The 20 housing characteristics are given equal weight. We currently lack adequate information to demonstrate that any particular housing characteristic is more hazardous and deserves extra weighting.

What are the most common problems across the nation in 2015?
The most common problems were signs of roaches (12%), signs of rodents (10%), water leaks from the outside (10%) and inside (9%). Other frequent problems include damaged interior walls (6%), foundation problems (5%), and roofing problems (4%). However, there is variation across the MSAs so these may not be the most common problems in every MSA.

What is NCHH doing about all this?

  • Research: NCHH conducts cutting-edge research to identify not only problems but also best practices and solutions. Visit to learn more about NCHH’s research.
  • Information, Materials, and Capacity-Building: NCHH produces content and educational materials for consumers, professionals, and public decision makers. NCHH staff are also available to provide technical assistance to healthy homes practitioners, researchers, and decision makers interested in best practices for improving housing quality. If you have additional questions after reviewing NCHH’s resources section, visit “Ask NCHH” at
  • Policy and Advocacy: We are fighting for stronger legislation, regulations, and enforcement by Congress, federal and state agencies, and other key bodies. For more information, visit

Why aren’t the data all from the same year?
The national American Housing Survey data are collected every two years, but metro areas are sampled more periodically. The current strategy is to survey the 15 largest metro areas and a sample of 10 other large metro area every two years. The strategy began in 2015 and continued with the 2017 sample. Prior to 2015, a less consistent pattern of selecting metro areas was in place.

Wouldn’t jurisdictions with older data be unfairly penalized?
To ensure that locations were not penalized in the rankings for having older data, we compared each jurisdiction’s data to the most similar national year of data.

Why do many of the metrics have numerical rankings but don’t have “healthy” or “unhealthy” icons?
Only conditions that are significantly different statistically from the national average for a given survey year are noted with a green or red house icon.

How can my city make use of this data?
Municipal governments can use this data to engage in the following activities:

  • Use information to demonstrate need for healthy housing code enforcement.
  • Present information to other agencies within government to start dialogue on healthy housing issues.
  • Review strengths and areas for improvement with news outlets – demonstrate how the city has started to address housing problems or where they need more support.

NGOs and community groups should use the State of Healthy Housing for the following activities:

  • Analyze data for strategic planning and areas on which to focus.
  • Present information to government agencies.
  • Encourage more frequent, detailed data collection similar to this.
  • Provide educational materials and resources to community members on housing hazards of concern.