Drainage devices and system

A building drainage system for use under a floor of a building, the building drainage system comprising:

• the floor;
• a foundation wall;
• a footing located below the foundation wall;
• a first drainage device on the footing adjacent the foundation wall;
• a second drainage device on the footing adjacent the foundation wall and spaced apart from the first drainage device, the first and second drainage devices laying in an end-to-end relation on a straight section of the foundation wall and the footing and defining a gap therebetween;
• and
• a bridge drainage device disposed on the first and second drainage devices on the footing adjacent the foundation wall, the bridge drainage device bridging the gap between the first and second drainage devices and spaced apart from the foundation wall and the footing to permit water to flow along the foundation wall and along the footing under the floor beneath the bridge drainage device, the bridge drainage device including:
• a wall member for bridging the gap between the first and second drainage devices and configured to prevent blockage of the gap by the floor during installation of the floor, the wall member having a first surface facing away from the footing and foundation wall and a second surface facing toward the footing and the foundation wall, the wall member comprising a wall section for facing the foundation wall and a footing section for facing the footing, the footing section being disposed under the floor and configured to space the floor apart from the footing, the wall member being free of protrusions for nesting with at least one of the first and second drainage devices, the wall section and the footing section engaging the first drainage device and the second drainage device.