Certainteed Adds Flyash to Fiber-Cement Siding

CertainTeed Corporation has altered the formulation of its fiber-cement siding lines to add recycled flyash. CertainTeed WeatherBoards and ColorMax fiber-cement siding lines now include 30%–50% flyash in addition to wood fiber, portland cement, and other additives. Cement is energy intensive to produce, and the use of flyash, a waste product produced by burning coal, has reduced the amount of cement required in some concrete applications in buildings. However, that is not the case with the new fiber-cement formula, CertainTeed’s Lisa Santerian told

EBN, with the flyash instead standing in for sand. According to Santerian, the wood fibers come from sustainably managed forests certified by an unspecified program. CertainTeed bills the new fiber-cement formula as lighter weight, lower density, and equally durable compared with its previous version.