High Albedo Roof Materials

High albedo materials are those materials that have high reflectivity and low absorptivity.

High albedo roof materials.

Coolroof paint is a high albedo product having solar reflectance of 0 95 and emissivity as high as 0 91. High albedo materials can save cooling energy use by directly reducing the heat gain through a building s envelope direct effect and also by lowering the urban air temperature in the neighborhood of the building indirect effect p p this project is an attempt to address high albedo materials for buildings and to perform measurements of roof coatings. The solar reflective index sri for coolroof is 122. New materials in high albedo roof coatings this section describes the main innovation efforts around high albedo or cool coatings.

Reflective surfaces are a form of geoengineering. Reflective surfaces can deliver high solar reflectance the ability to reflect the visible infrared and ultraviolet wavelengths of the sun reducing heat transfer to the surface and high thermal emittance the ability to radiate absorbed or non reflected solar energy. Tile roofs can be made of clay slate or concrete. The most well known type of reflective surface is the cool roof.

Commercial cool roof options include bright white membranes and white coatings. Other roof shingles can be coated at the factory or in the field to make them more reflective. In contrast to conventional roofs these kind are specifically designed to reduce internal building temperature by reflecting the sun s uv rays. Measures cr 1 and cr 2 examine the impacts of applying such a coating over a light gravel covered built up roof.

As one would expect albedo roofs are formulated with special high eminence materials that keep project a high level of thermal energy back into the atmosphere. Coolroof heat reflective paint has sri value of 122 as per astm leeds standards for green buildings. In the morning and in the late afternoon the high albedo materials were as cool as the air itself. While conventional roofing materials warm up by an average 0 055 degrees c w m sup minus 2 the high albedo surfaces warm up by an average 0 015 degrees c w m sup minus 2 doi 10 2172 7000986 journal number volume place united states year wed jan 01 00 00 00 est 1992 month wed jan 01 00 00 00 est 1992.

These materials are preferred during the development of smart cities and green buildings because they help neutralize the urban heat island effect in a natural manner. Tiles can be glazed to provide waterproofing or coated to provide customized colors and surface properties.