How Cool Roofing Works

Cool roof shingles tiles and slate may be coated with special granules to give them better solar reflectance.

How cool roofing works. Green building council and the department of energy building technology program base their respective cool roof credentials on a roofing material s ability to reflect the sun solar reflectance and release absorbed heat emissivity. Cool roofs can be made of a highly reflective type of paint a sheet covering or highly reflective tiles or shingles. Cool paint is made of highly reflective type of paint by emissivity aqueous coating based on acrylic resins. On the other hand cool roofs stay cooler in the sun and transmit less heat into the building.

It begins with the rafters and continues on in layers of protection that prevent water and the wind from damaging your home. The coolness of a roof is determined by two properties of roofing materials and their combined effects on temperature. On top of the rafters your roof has plywood followed by sheathing a material that s designed to protect your home from moisture. Roof temperature is rated via solar reflectance and thermal emittance with ratings ranging between 0 and 1.

While the term cool roof is sometimes used to describe any roofing surface that is cooler than a standard rooftop green certification programs such as leed energy star the u s. Solar reflectance ability to reflect sunlight. The right underlayment for your roof will keep moisture cold weather and stifling summer air out giving your roof a longer life. How your roof works your roof is not just made up of a few shingles.

A cool roof is one that has been designed to reflect more sunlight and absorb less heat than a standard roof. Whereas darker traditional roofing materials absorb sunlight the reflective surfaces of a cool roof reflect it away. Thermal emittance ability to cool down by emitting heat that is absorbed. Today there are many options for roofing underlayment materials rubberized asphalt to organic fiberglass to synthetic.

The heavy mass of cool roof shingles and tiles can also provide some degree of thermal protection by absorbing and blocking heat during the day and releasing heat throughout the night. Cool roofs are designed to lower the temperature of your home in summer months making you more comfortable and potentially reducing your energy bill. Cool roofs achieve this by reflecting some of the infrared ir light from the sun. Reflective metal roofing may also cool high slope roofs.

A cool roof is a roofing system that delivers higher solar reflectance the ability to reflect the visible infrared and ultraviolet wavelengths of the sun reducing heat transfer to the building and higher thermal emittance the ability to radiate absorbed or non reflected solar energy than standard designed roofing products. This results in lower absorption of solar heat and a cooler roof.