How Cool Roof Works

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.

How cool roof works. Cool roofs reduce the thermal radiation of heat into the atmosphere convection of heat into outside air and the conduction of heat into the building. The right underlayment for your roof will keep moisture cold weather and stifling summer air out giving your roof a longer life. The surface of a cool roof reflects more sunlight and releases more heat than a so called hot or dark roof. You can usually make a new or existing roof cool by selecting the appropriate surface.

White or special cool color roofs absorb less sunlight stay cooler in the sun and transmit less heat into the building. Coatings are like very thick paints that can protect the roof surface from ultra violet uv light and chemical damage and some offer water protection and restorative features. A higher albedo means that a roof has a higher ability to reflect the sun s rays and thus reflects more sunlight than traditional roofs. Compared to traditional roofs a reflective roof has a high albedo or solar reflectance.

It begins with the rafters and continues on in layers of protection that prevent water and the wind from damaging your home. Traditional dark colored roofing materials strongly absorb heat from sunlight making them warm in the sun and heating the building. 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.

This lowers urban air temperatures and mitigates the urban heat island effect. How cool roofs work traditional dark colored roofing ma terials absorb sunlight making them warm in the sun and increasing the need for air conditioning. A cool roof is a roof designed to maintain a lower surface temperature in bright sunshine than a traditional roof source. Cool roofs are designed to reflect sunlight while absorbing less heat.

Whereas darker traditional roofing materials absorb sunlight the reflective surfaces of a cool roof reflect it away. Cool roof coatings are white or special reflective pigments that reflect sunlight. How your roof works your roof is not just made up of a few shingles. There are many types of roof systems available but the surface exposed to the sun is the one that determines if a roof is cool or not.

On the other hand cool roofs stay cooler in the sun and transmit less heat into the building. Historically cool roofs have been either white or some other lighter shade color. It also slows the formation of ground level ozone and smog.