Phoenix, AZ. Jerry Brown, a 47-year veteran of the roofing industry says when he teaches class on roof repairs and restoration, he likens it to how we should be protecting our skin.
“The primary purpose of roof coatings in Arizona is to protect the roof from UV degradation and cool the roof. This is like you putting sun blockers on your skin to prevent damage and even skin cancer. The sun destroys roofs with its UV radiation and the heating and cooling effects of thermal shock also damage them so cool coatings, typically white, are of equal importance too.”
Brown, who heads WRECORP, a roof consulting firm, teaches classes to the roofing industry through the Arizona Roofing Contractors Association (ARCA) on roof installation, repairs and restoration. He says roofs are very much like human skin care in this regard. “You get damage on a roof like a crack or a hole from hailstones, you repair it like dressing a wound. In this case you use a polyester fabric and three course it with coatings. Jerry believes that with the proper application and timing of the application of roof coatings you can extend the life of most roof systems by double.
“Similarly, you see what prolonged immersion in water does to the skin making it weaker. Ponding on flat roofs will weaken the roofs and allow the water to quickly seek out holes and cracks and, once under it, will quickly cause damage.”
Brown said that it is very important that restorations of roofs are done with coatings that provide high adhesion, high UV and waterproofing protection, especially in his state which has such wild fluctuations in weather conditions, including hail storms.
With topcoat choice being critical, Brown strongly favors acrylics which can give up to 20 years of service. In his opinion “Silicones have proven to be too brittle, yellow and pick up dirt too easily. Silicone coatings for roofs are not like the silicone caulk you buy in a store to fill holes and cracks at all. They are a totally different formulation.”
Recent pull tests involving Castagra’s veggie-plastic Ecodur on asphalt emulsion, along with a leading acrylic and a top brand of silicone coating, demonstrated Ecodur’s superior adhesion. The acrylic came in second and the silicone third.
“Adhesion is immensely important, especially on roofs prone to ponding where water can sit around for days. In winter, freeze thaw can increase the hidden damage rapidly. Water has its maximum expansion at 3.98 degrees Centigrade, or 39.16 Fahrenheit.”
Castagra CEO, Peter Roosen, who invented the veggie-plastic coating made from castor oil and gypsum, said that right from the start of its development, he realized that adhesion would be a major factor in enhancing the protective qualities of roof coatings.
“Ecodur molecularly bonds with cellulosic materials. There is no better bond than that so wood substrates are the ultimate for adhesion.
“Jerry likens roof coating maintenance to human skin care. In the case of human’s protective outer layer skin, its adhesion is absolute, except, of course, when physical damage takes place. Human skin is constantly shedding dead skin and replacing with new cells.
“A roof coating, on the other hand, permanently loses about 1/2 mil of thickness a year, so, for many roof coatings of 20 mil thickness, it’s not surprising they don’t usually last much longer than two decades and often far less. The industry believes that 30 mils is the minimum acrylic coating thickness that should be used.
“Human skin, over time, loses its elasticity and this is where Ecodur scores heavily against the competition. Long term it retains its elasticity for the lifetime of the coating. It also retains its hardness, so important in hailstone prone areas.
“Intense and prolonged UV on Ecodur merely creates a molecule deep layer of oxidation and a minor change in color without affecting performance at all,” continued Roosen.
“Roof coating and membrane technologies have come to the forefront in recent years as the pressure grows to make roofs part of the response to climate issues. We have conventionally coated membraned roofs, cool roofs, green roofs and now blue roofs.
“Aside from rainfall, snow, and sun protection, they have firmly entered the new era making a very real difference on the bottom line through lowered HVAC costs, helping to lower city heat sink effects, and even rainfall runoff mitigation.
“But, as we are taken further and further into the important equation of climate issues, I rather like Jerry’s analogy of treating them like human skin to keep these benefits going even further into the future with proper care against the elements we encounter all the time. It’s plain common sense,” Roosen concluded.