Waking Up to Climate Change

Cool Roofs, Sleep, & Health In Baltimore City

Much of the housing in Baltimore City consists of rowhomes—townhomes capped by a heat-absorbing roof. In the summer, these roofs lead to hot temperatures in the top floor of rowhomes, where the bedrooms are often located. Light-reflecting “cool roofs” may significantly reduce temperatures in rowhouse bedrooms, reducing energy use, and perhaps improving health for occupants. This project will investigate associations of cool roofs with temperatures and health in Baltimore City.

Climate change is a defining challenge of our time. The effects of rising temperatures are pronounced in cities, which are dominated by heat-absorbing surfaces and have limited greenspace. This produces the urban heat island—the warming of an urban area compared to surrounding areas. Because heat absorbing surfaces and greenspace are not evenly distributed throughout a city, the urban heat island is exacerbated in low-income areas, which may lead to important health disparities.

Cool roofs may be a simple public health approach to mitigate the urban heat island. Many cities including Baltimore already encourage cool roofs to reduce energy consumption, but we propose that their benefits may be broader. High indoor temperatures degrade indoor air quality and reduce sleep quality, which is associated with poor downstream health outcomes (e.g., cardiovascular disease, depression). Furthermore, implementing cool roofs on a large scale may yield neighborhood-level temperature reductions.

Partnership with the City of Baltimore and City residents will support several additional installations of cool roofs and guide our evaluation of the effects on temperatures and health by examining the “before” and “after” of cool roof installation. We will also use mathematical models to understand the optimal spatial distribution of cool roofs to minimize health disparities and estimate their economic benefits.

This project will improve our understanding of the benefits of cool roofs that could be deployed in cities globally to mitigate the impacts of climate change and improve health equity.

Primary Investigators

• Kirsten Koehler, PhD
  Environmental Health and Engineering,
  Johns Hopkins Bloomberg of School of Public Health
• Adam Spira, PhD
  Mental Health,
  Johns Hopkins Bloomberg of School of Public Health

Co-Investigators & Partners

• Jura Augustinavicius
  Mental Health,
  Johns Hopkins Bloomberg School of Public Health
• Benjamin Zaitchik
  Earth and Planetary Sciences,
  Johns Hopkins Krieger School of Arts and Sciences
• Peter DeCarlo
  Environmental Health and Engineering,
  Johns Hopkins Bloomberg School of Public Health
• Emmanuel Drabo
  Health Policy and Management ,
  Johns Hopkins Bloomberg School of Public Health
• Genee Smith
  Environmental Health and Engineering,
  Johns Hopkins Bloomberg School of Public Health
• Sara Benjamin-Neelon
  Health, Behavior and Society,
  Johns Hopkins Bloomberg School of Public Health
• Meredith McCormack
  Pulmonary and Critical Care Medicine,
  Johns Hopkins Medicine
• Tamar Mendelson
  Mental Health,
  Johns Hopkins Bloomberg School of Public Health
• Susan Sherman
  Health, Behavior and Society,
  Johns Hopkins Bloomberg School of Public Health
• Alice Kennedy
  Baltimore City Department of Housing and Community Development
• Lisa McNeilly
  Baltimore City Office of Sustainability