Costs for maintenance and repair of conventional reinforced concrete (RC) buildings and structures have become a serious economical, ecological and social problem. A large percentage of worldwide infrastructure needs repair measures. This situation motivates great care when developing new construction materials, such as Fiber-Reinforced Concrete (FRC), whose enhanced toughness contributes to more durable structures. In fact, fibers could be introduced in RC structures to reduce the cracking phenomena thus helping the structural durability. In the present paper, fracture behaviour and water permeability of fiber reinforced concrete are studied. The effect of different crack openings is analysed in order to study its influence on the mechanism of ingress of water.