IS 3224 covers corrugated fibre cement sheets (formerly called AC sheets) for roofing and cladding. Modern versions are asbestos-free, using cellulose or synthetic fibres instead. Widely used for industrial sheds, warehouses, and low-cost housing roofing in India.
Specification for corrugated fibre cement sheets (asbestos-free) for roofing and cladding, covering types, dimensions, strength, and weathering requirements.
Key Values
Standard thickness6.0 mm (most common)
Standard width1050 mm (effective cover 920 mm)
Standard lengths1525, 1830, 2135, 2440, 2745, 3050 mm
Practical Notes
! Modern fibre cement sheets are asbestos-free — but older buildings may have asbestos cement sheets. Handle with care during demolition.
! Minimum roof slope for fibre cement sheets is 10° (1:5.7). Flatter slopes cause leakage at laps.
! Use J-hooks and bitumen washers for fixing — nail holes without washers leak.
! Fibre cement sheets are brittle and cannot support foot traffic — use crawling boards for roof maintenance.