In NCCA Tool Kit # 26, “Factors Influencing the Long-Term Performance of Prepainted Metal Building,” an emphasis was justifiably placed on the selection of materials. That selection process starts with a substrate that must provide the corrosion-resistant properties for the environment in which the prepainted product will be used, probably for decades. Whether the specifier is considering steel or aluminum, the mechanical properties of the material are of paramount importance. After all, all prepainted metal is post-formed, so the substrate, as well as the paint system, must be able to withstand the rigors of the fabrication process. With a steel substrate, it’s the thickness of the metallic coating layer; with hot-dipped galvanized steel, it’s the zinc; and with Galvalume®, it’s the Zn-Al metallic blend that needs to have an adequate thickness to provide the necessary lifetime and level sacrificial of galvanic properties. There are many parameters to consider. Continue reading
We are now a few decades into the era of cool metal roofing. “Era” is probably the wrong word, because cool metal roofing is here to stay. Many coatings producers and metal roofing manufacturers in North America now offer the benefit of cool roofing as a part of their standard product portfolio.
As “special” becomes “standard,” it is easy to assume that cool roofing is on autopilot and that nothing more needs to be done. Although in a practical sense this is mostly true, it is good to remember that research continues wherever energy savings is the goal, and cool roofing is included in this research.
Consider the following: Continue reading