Fiber-cement roofing shakes were widely marketed during the 1990s, especially in the West, as a fire-resistant substitute for wood shakes. Some manufacturers, including American Cemwood of Albany, Ore., were so confident of the durability of their fiber-cement shakes that they offered a 50-year warranty. Within three to five years of installation though, many fiber-cement roofs — which are made from a mixture of Portland cement and wood fiber — began to deteriorate. "As time went on, they would turn to the consistency of oatmeal," says Michael Satran, a Portland, Ore., roofer. His contracting company, Interstate Roofing, installed fiber-cement shakes made by both American Cemwood and Re-Con, a Canadian manufacturer. "The shakes would crumble in your hand," says Satran. "The freezethaw cycles would tear