Comparing Cooling Costs and Surface Temperature Reductions
Generally, all colored and traditional roofing materials have extremely low reflectivity values. Most roofs absorb a tremendous amount of heat by nature of their materials and colors. Even tiles that are advertised as “Cool” tiles generally have Total Solar Reflectance values below .40. The REFLECT-TEC System provides increased TSR values and can lead to cooling cost energy savings. Cooling cost energy savings and surface temperature reductions will vary based on:
Comparing energy use on colors that are different than the color previously applied to a homeowner’s home will give inaccurate results. Even though REFLECT-TEC is typically over 200% more reflective in dark colors compared to traditional paint in the same color, darker colors will inherently absorb more infrared radiation leading to increased heat build-up and lighter colors will reflect more infrared radiation leading to decreased heat build-up. When comparing dark colors to the same or similar color in REFLECT-TEC, these darker colors will yield higher savings (The increase in reflectivity with REFLECT-TEC for dark colors is more substantial than the increase in reflectivity for lighter colors).
Comparing the same color of traditional paint to REFLECT-TEC in lighter colors, the percentage of increase in reflectivity, while still substantial, is lower and therefore will yield lower cooling cost savings. In order to obtain accurate comparisons, the color chosen must be the same or similar to the color being used for comparison. If a customer chooses to go from a light colored traditional paint to REFLECT-TEC in a darker color, the percentage of savings may not be as high. If a customer goes from and extremely light color to a dark color in REFLECT-TEC, there may not be any surface temperature reduction and in fact be an increase in cooling costs. Consequently in order to make a proper comparison and analysis of surface temperate reductions and cooling cost savings, the color chosen by the homeowner needs to remain in the same family of color. (Colors are typically classified as light, medium or dark.) Any comparison in surface temperature reduction and cooling cost savings needs to be done with the same or similar color. The proper analysis should always be to compare the original color to the same or similar color in REFLECT-TEC.
Comparisons must be for periods when experiencing the same or similar climate conditions in order to be accurate.
LANDSCAPING AND SURROUNDINGS
Changes in the shading from landscaping and surroundings on walls, windows, or roofs will affect surface temperatures and cause energy use comparisons to be inaccurate.
Changes in utility rates will cause comparisons to be inaccurate if dollar amounts are used for comparison purposes. Comparisons should be done on units of energy usage only.