Energy Guide

4426 Hugh Howell Road Suite B323 ~ Tucker, Georgia 30084
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White Paint, Reflective or Cool Roof Coatings or Heat Blocking Coating! ... Isn't it all the same? NO
Heat energy from Sun arrives and reaches the earth as solar radiation. Solar radiation (Electromagnetic Waves) loads on to external
surfaces (like Roofs, Tanks, Equipment, etc..) in three (3) main ways:
1. Infrared (53% of the Sun’s Heat load is Infrared)
2. Visible Light (44% of the Sun’s Heat load is Visible Light)
3. Ultraviolet (3% of the Sun’s Heat load is Ultraviolet)
For a paint or a coating to be effective, it must be able effectively handle all 3 aspects of Solar (Sun Heat) loading. Lets briefly discuss
the options.
White Paint
My personal opinion when asked about the real world performance ability of white paint to keep surfaces cool, is that
“ If solving the world’s energy crisis, heat island build up and Carbon (CO2) emissions was as simple as painting
surfaces white or using white colored materials that depending merely on reflection as a byproduct of being white in
color, then the world would have painted every external surface white a long time ago and thus would have avoided
the reported Global Warming & Heat Island crisis’’.
When you consider using white colored paint or white coatings that depend only on their whiteness (meaning being
white in color) for reflectivity, these products are only able to impact one (1) of the three (3) ways that solar (sun) heat
loads and that is the Visual Light wave. As shown above, Visual Light is only about 44% of the total heat that comes
from the sun. White paint doesn't deal with the other important aspects of sun heat loading, which is infrared or
ultraviolet (which is 56% of the sun heat load). So, whilst white paint will offer some initial benefits to reducing the
heat build-up on say your metal, Asphalt or Concrete roof system, Equipment, Tank, or whatever the external surface
item is, for a short period of time, White paint typically will lose any long-term effectiveness once the surface gets
dirty and thus the long-term benefits are significantly reduced and as time goes by, our experience is that they
provide very little value. Infrared waves cannot be reflected with white paint and thus with paint you can only impact
44% of the heat that is trying to load and the surface must be white and clean for white paint to provide lasting
benefit.
Reflective or 'Cool Roof' Coatings
These coating systems whilst also being mostly white or very glossy colored surfaces, are very similar to white paint
in that they typically impact just the visible light waves coming from the sun, which again is only 44% of the total heat
that loads from the sun. The reflection / reflectivity of sunlight is important, as it will reduce some heat load, but
typically, the reflective coating will only work when they are shinny or nice and clean. The problem is, however,
external surfaces like roofs, tanks, equipment, warehouse, do not stay clean, they get dirty or etched from UV
degradation or acid rain, etc… When this happens, like white paint, they immediately start to lose performance
effectiveness, until basically they stop working.
For example, a white coated / painted car that is new and shiny is highly reflective, and initially cooler on the surface
than a black car, because the shiny white reflective car can initially bounce or reflect 44% of the solar (Sun) heat that
tries to load. But, in a short period of time, after the white car (used in this example), becomes etched from UV and
acid rain, you can touch the surface of the white car and it is as hot as a black car. IM sure that you have