In April, we reported that the mayor of Los Angeles wanted to add cool roofs to the city’s building code – now it’s official.
This week, the Los Angeles City
Council unanimously passed that update to the building code, making it the first major US city to do so. Going forward, when homeowners replace their roof it must be "cool" and all new homes must include them. NYC also has a cool roofs program, but it’s not mandatory.
The report, Bright Roofs, Big City, which analyzes the potential benefits of widespread adoption of cool roofs in Los Angeles, finds that besides reducing the heat island effect, $30 million would be saved on energy bills and greenhouse gases would be cut by the equivalent of taking 7 million cars off the road for a year – 80% of LA’s carbon footprint.
Cool roofs – which are usually white, but can also be shades of gray, red or other colors – reflect so much sun that they can be 50°F cooler
during the heat of summer, keeping building interiors several degrees Fahrenheit cooler.
“Cool roofs are one of the quickest and lowest cost ways we can reduce our global carbon emissions and begin the hard work of slowing climate change,” said Steven Chu, former Secretary of the Department of Energy, as he directed the agency to install them during renovations.
Temperatures in LA are expected to be between 3.7°F and 5.4°F higher by 2050, with triple the number of “extreme heat” days above 95°F in downtown LA, according to research by University of Calfornia/ LA research.
the city cooler not only cuts greenhouse gas emissions by reducing the
heat island effect, it will reduce heat-related
hospitalizations, improve air quality by reducing ozone formation,
make power outages less likely and cut homeowner energy bills.
Incentives are in place so that cool roofs won’t cost more than traditional roofs.
Cool roofs are in California’s first-in-the-nation mandatory Green Building Standards Code, CALGreen, which took effect in 2011.
The Global Cool Cities Alliance is working to spread cool roofs worldwide. They want 100 major cities to sign on to becoming "Cool Cities" by 2015: