How Solar-reflective Walls Help Green the Building

By Cass Jacoby. 

Sherwin-Williams Coil Coatings becomes a licensee of the Cool Roof Ratings Council (CRRC) wall program, read on to learn what this means. 

You might have heard of cool roofs, which are roofs painted lighter colors to reflect sunlight rather than absorb it, but have you heard of solar-reflective walls? Like cool roofs, solar-reflective walls work to cool themselves by efficiently emitting any heat that was absorbed. Thus, the exterior wall surface stays cooler and reduces the amount of heat conducted into the building, providing many of the same benefits that a cool roof does to the home, including: 

• Increasing occupant comfort by keeping the building cooler during hot summer months. 

• Reducing the need for air conditioning and cutting energy costs accordingly. 

• Improving grid stability and decreasing peak energy demand by reducing air-conditioning needs during the hottest part of the year. 

• Reducing the urban heat island effect by limiting the amount of absorbed heat in urban areas and lowering air temperature. 

• Improving air quality by reducing CO2, nitrogen oxides (NOₓ), sulfur dioxide (SO₂), and other emissions associated with fossil fuel-generated electricity used for air-conditioning through the reduction in outdoor air temperatures, as well as slow the production of ground-level ozone, which contributes to smog formation. 

How do solar-reflective walls work? 

The exterior of buildings is painted, or in the case of metal, pigmented within the factory to have hues that are “cooler” and reflect more sunlight. Solar-reflective walls are available in a variety of lighter and darker colors that use reflective “cool” pigments, these pigments are designed to additionally be reflective of infrared light without affecting the color of the product. 

Less sunlight hits the walls of a building over a roof throughout the year, however, walls often have less insulation than roofs, usually having about half the resistance to heat flow than that of a roof. The combined factors of less sunlight and less insulation ultimately result in similar savings from solar-reflective walls to that of cool roofs. 

Solar-reflective walls are evaluated using the same two properties as cool roofs – solar reflectance and thermal emittance. The CRRC measures these two properties and publishes the results in the Rated Wall Products Directory. Sherwin-Williams Coil Coatings has proudly been added to the Rated Wall products directory, providing sustainable wall coatings that make going green easy and accessible. 

Learn more about Sherwin-Williams in their RoofersCoffeeShop Directory or visit makemorewithmetal.com.