Understanding how much sunlight is reflected and how long the reflectance lasts, is an important concept to understand when considering a cool roof.  The Energy Star® Roof Products Program, sponsored by the EPA, maintains a list of roofing products that demonstrate initial solar reflectivity greater than 65% and retained reflectivity of greater than 50% after three years of weathering.  Of all the products rated, only the Duro-Last membrane has retained reflectivity of greater than 85% after three years of weathering.
      To understand how Duro-Last is able to keep its reflectivity is to look at the examples below.  The black balloon represents a majority of all existing flat roofs in the United States.  When it comes to cool roofing most building owners who have black roofs, have a white coating installed over the existing roof.  This is illustrated by the second balloon.
      The coated balloon appears to be white, that is until the balloon is expanded and contracted a few times.  Expanding and contracting the balloon represents the expansion and contraction that roofs face daily.  Putting a white coating on a black roof will eventually crack and peel exposing the original black roof and negating all roof reflectivity.
      The last balloon is white throughout, Duro-Last roofing system, and this balloon can expand and contract without loosing its reflectivity and integrity.  This ability is why Duro-Last is a charter partner of the EPA Energy Star Roof Products Program.