Durability and sustainability is essential serviceability concern for alkali-activated composites used in construction. The incorporation of natural fibers in alkali-activated materials is beneficial considering its availability, low density, and acceptable mechanical performances. There are two types of natural fibers which are plant and animal fibers. The plant fiber composes of cellulose, hemicellulose, lignin, pectin, and waxy substances. The durability of natural fiber-reinforced alkali-activated composites influences by several factors including type and content of fiber, dispersion and size of fiber, fiber modification, fiber moisture content, fiber alkaline degradation, and fiber mineralization. Besides, this chapter indicates the durability of natural fiber-reinforced alkali-activated composites in terms of crack resistance and toughness, high-temperature resistance, wet/dry cycles, freeze-thaw cycles, chemical resistance, and carbonation resistance.
