I was doing some research the other day on types of roofing materials and the pros and cons to having a reflective roof in this climate. There are an abundance of reflective roofing materials, from shingles with reflective particles in them (that allow you to use darker colours but still have the heat reflection benefits), recyclable vinyl roofs, sheet metal roofs, reflective membranes/barriers of various types, as well as “paint on” types of products for existing roofs. Interestingly, my husband remembered that his mother’s business had applied one of those paint-on products years ago to the existing flat black roof and it made a big difference in the temperature (i.e., no longer melting his shoes to the roof!) when he went up to clean out the swamp cooler.

What I found out, however, was in this climate the advantage of a reflective roof would be minimal. The average “cooling degree days” (i.e., how many degrees a year you are cooling to get to 65 degrees F.) is 458. Compare that, with, say, Phoenix, that has nearly the same rainfall as we do annually (i.e., desert) but has 4162 cooling degree days! You can look up your heating/cooling degree days on this website.

There does still seem to be some benefit to having a lighter coloured roof in this climate, so we probably will go with that but perhaps not worry about the speciality products. I’m not sure what the cost comparison is between products, which would be the biggest factor, but it does seem to make more sense at this point to concentrate on high-quality windows and insulation, with a long-lasting shingle (reflective or not).

There is a fair amount of helpful information on roofing material types and benefits at the Roofing Contractor website.