Among the many worries of a building owner or manager, staying cool in the summer and cutting costs are two things which always present themselves. Unfortunately, they seem to be in complete contradiction of each other. However, with the growing popularity and availability of “cool roofs,” this might not be the case anymore. While cutting costs and staying cool might seem a little too good to be true, it’s based on the scientific concept of albedo.
What is Albedo?
Albedo is the effect certain materials have which causes heat and light to reflect off of those materials instead of being absorbed by them. For instance, if a lake is covered by ice and snow, the heat from sunlight will reflect off the snow, when it would have been absorbed by the water. This phenomena is called albedo; or high solar reflectance. When applied to buildings, the idea is that cool roof material will reflect much of the sunlight and heat which would normally be absorbed through the roof and into the building. This leads to a great reduction in cooling costs as air conditioning is not needed as much.
Urban Heat Island
Albedo has been explored to help reduce the effects of urban heat islands. An urban heat island is an area where the close proximity of buildings, people, and machines create higher than expected temperatures. For instance, temperatures in downtown New York City are consistently recorded as higher than in rural areas surrounding the city. Each person and each machine uses energy which is usually released as heat. With enough people in a small enough space, an urban heat island is created. Cool roofs were developed to try to address urban heat islands, by diminishing the amount of solar heat absorbed by these already warm buildings.
Costs of Cool Roofing
Though costs will differ depending on many variables like location, local laws, and climate, the Environmental Protection Agency estimates the increased cost for these new materials is between 0 and 10 cents per square foot, which is in turn offset by the savings. According to epa.gov:
A California study found that cool roofs provide an average yearly net savings of almost 50 cents per square foot. This number includes the price premium for cool roofing products and increased heating costs in the winter as well as summertime energy savings, savings from downsizing cooling equipment, and reduced labor and material costs over time due to the longer life of cool roofs compared with conventional roofs.
Although initially installing the cool roof products may be more expensive than traditional roofing materials, the savings will come from reducing air conditioning expenses and a longer lasting roof. This is an investment of sorts, in which the rewards are reaped in the long haul.
When choosing a roof, consider how it will affect the other aspects of your building, such as heating and cooling systems. If you are considering cool roofing for your home, let the professionals at All Weather Tite, Marlborough, MA help you make the right selection. You can contact us for a free quote, or with any questions about our products or service.