US Patent 10487472 Drainage devices and system

A drainage device for use under the floor of a building to facilitate drainage of water along a foundation of the building under the floor. The drainage device can include a corner drainage device that is capable of assuming a number of near 90 degree shapes so that the drainage device can be easily fitted to the corner of the foundation. A bridge drainage device permits more rapid installation of the drainage devices. The bridge device can be used to bridge between two drainage devices so that it is not necessary to cut the drainage devices precisely to fit on a footing of any selected length.