Dark Roof’s Summer Cooling Penalty is a Deciding Factor
Cool roofs reflect the sun’s energy and reduce air conditioning loads in the summer, so do dark roofs absorb energy in the winter and reduce heating costs? In northern regions where heating costs are significant, can dark roofs be energy efficient? Some building professionals specify dark absorptive membranes for northern cities like Chicago and Minneapolis believing that they are lowering their clients heating costs and lowering year round energy costs.
An analogy, only slightly tongue in cheek, would be to ask if Chicagoans walking along Michigan Avenue in the winter wear dark clothes to stay warmer? Or do dark colored cars outsell light colors in the Windy City?
So, do dark roofs help improve building energy efficiency in northern cities? Let’s take a look at the arguments.