White roofs have gained cachet as a solution to the urban heat island effect. But in places where there are more cold days than hot, a white roof that reflects warming sunlight might not make the best sense, according to this piece.
"By having information on the different roof choices, building owners can choose the roof that is best for their location and climate, and that best solution isn't always white.
The Cool Roof Rating Council admits to a "winter penalty" when cool roofs are installed in northern climates. An article in the April edition of Maintenance Solutions magazine that was penned by the CRRC states, "Heating costs may increase slightly for buildings located in cooler regions." CRRC's justification for increasing heating costs and greenhouse gasses was that days (sunlight hours) are longer in the summer than they are in the winter, thus more energy is consumed to cool a building than to heat it.
The article failed to mention spring and autumn. However, information gathered from the U.S. Department of Energy clearly demonstrates that heating is a much more significant factor in energy usage than cooling. For instance, Grand Rapids, Mich., has 7,153 heating degree days versus 508 cooling degree days per year, which means heating equipment runs approximately 14.3 hours for every one hour that cooling equipment runs."
"...To illustrate this point, I've chosen three major U.S. cities and provided analyses of energy and carbon footprint models, all generated using the DOE's cool-roof calculator, to help lend some clarification and hopefully dispel some growing cool-roof myths.
• Boston, Mass.: 5,841 HDD versus 646 CDD
• Grand Rapids, Mich.: 7,153 HDD versus 508 CDD
• Albuquerque, N.M.: 4,361 HDD versus 1,211 CDD
Due to the overwhelming amount of heating degree days and positive winter heat gain in these locations, in all instances, energy consumption and carbon emissions are fewer with a dark roof surface than with a reflective surface. This is true even as far south as Albuquerque. It is also important to note that increased insulation dramatically reduces energy consumption in every model."
FULL STORY: A White Roof Isn't Always the Right Roof
How Rotterdam’s Green Rooftops Fight Urban Heat
An elevated park in Rotterdam shows how green roofs can cool cities and create public parks in tight quarters.
To Combat Rising Heat Deaths, Phoenix Creates Heat Response and Mitigation Office
As more extreme temperatures lead to an alarming rise in heat-related deaths across the country, Phoenix is taking action with the nation's first public heat response office.
Debate Continues Over Benefits of White Roofs
Researchers at the Lawrence Berkeley National Laboratory recently completed an economic analysis of white roofs versus their green and black counterparts. The debate over the relative merits of white versus green roofs is far from over, however.
Pennsylvania Mall Conversion Bill Passes House
If passed, the bill would promote the adaptive reuse of defunct commercial buildings.
Planning for Accessibility: Proximity is More Important than Mobility
Accessibility-based planning minimizes the distance that people must travel to reach desired services and activities. Measured this way, increased density can provide more total benefits than increased speeds.
World's Largest Wildlife Overpass In the Works in Los Angeles County
Caltrans will soon close half of the 101 Freeway in order to continue construction of the Wallis Annenberg Wildlife Crossing near Agoura Hills in Los Angeles County.
Eviction Looms for Low-Income Tenants as Rent Debt Rises
Nonprofit housing operators across the country face almost $10 billion in rent debt.
Brightline West Breaks Ground
The high-speed rail line will link Las Vegas and the Los Angeles area.
Colorado Bans No-Fault Evictions
In most cases, landlords must provide a just cause for evicting tenants.
City of Costa Mesa
Licking County
Barrett Planning Group LLC
HUD's Office of Policy Development and Research
Mpact Transit + Community
HUD's Office of Policy Development and Research
Tufts University, Department of Urban and Environmental Policy & Planning
City of Universal City TX
ULI Northwest Arkansas
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
