Volume per capita as a useful measure of residential space

Residential overcrowding has remained a persistent, low-level phenomenon in the United States over the past 30 years, and has been linked to negative personal health outcomes. A household is typically considered overcrowded if it has more than one person per room (PPR). The PPR measure, however, ignores variations in room size and does not accurately measure residential living space. To remedy this issue, we introduce volume per capita (VPC), a new measure that combines census, land use and building data to quantify the amount of residential space per person in cubic footage. We find that VPC correlates with three distinct measures of PPR (r² = 0.05–0.26), but has no relationship to population density. This suggests that PPR and VPC capture different aspects of living conditions, and that VPC provides a more direct measure residential space. In addition, because VPC can be calculated at the fine-grained spatial resolution of census blocks, it is an ideal measure by which to quantify residential space and understand overcrowding within metropolitan areas.