Fiber cement: Portland cement + sand + cellulose fiber, autoclaved. Profiles: lap/horizontal (HardiePlank), panel (HardiePanel), shingle, board-and-batten (HardieTrim). Thickness: 5/16 in (standard), 7/16 in (premium texture). Width: 5.25-12 in exposure. Fire: noncombustible, Class A. Wind: rated to 210+ mph. Warranty: 30-year finish (ColorPlus prefinished). Installation: face-nail with siding nails 16 in o.c., blind-nail with 6d galvanized. Gap: 1/8 in butt joints with caulk or H-mold. Cutting: carbide blade (fiber cement shears preferred — less dust). Dust: contains crystalline silica — respirator required per OSHA 1926.1153. CSI 07 46 46. Cost: $1.50-$5.00/sf material, $8-$16/sf installed. Competitors: Allura, Nichiha, Cemplank.