Many of the roofing products we use and recommend are available in lighter colors, or pure white in the case of some sealers. These light colors can significantly reduce the amount of heat that your roof absorbs - and greatly reducing your cooling costs. Energy Efficient and Environmentally Friendly!
Using Cool Roofs to Reduce Heat Islands
A high solar reflectance—or albedo—is the most important characteristic of a cool roof as it helps to reflect sunlight and heat away from a building, reducing roof temperatures. A high thermal emittance also plays a role, particularly in climates that are warm and sunny. Together, these properties help roofs to absorb less heat and stay up to 50–60°F (28–33°C) cooler than conventional materials during peak summer weather.
Benefits and Costs
Cool roofs provide a number of benefits beyond urban heat island mitigation, including:
- Reduced energy use: A cool roof transfers less heat to the building below, so the building stays cooler and uses less energy for air conditioning.
- Reduced air pollution and greenhouse gas emissions: By lowering energy use, cool roofs decrease the production of associated air pollution and greenhouse gas emissions.
- Improved human health and comfort: Cool roofs can reduce air temperatures inside buildings with and without air conditioning, helping to prevent heat-related illnesses and deaths.
Cool roofs deflect some desired heat gain during the winter. In general, though, cool roofs result in net energy savings, especially in areas where electricity prices are high.
Although costs will vary greatly depending on location and local circumstances, cool roof coatings on a low-slope roof might cost $0.75–$1.50 per square foot, while single-ply cool roof membrane costs vary from $1.50–$3.00 per square foot. The cost premium for cool roofs versus conventional roofing materials ranges from zero to 5 or 10 cents per square foot for most products, or from 10–20 cents for a built-up roof with a cool coating used in place of smooth asphalt or aluminum coating.
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
Interested in a cool roof to save both energy and money? Contact CD Kaller and we can discuss your options.