Abstract: A watertight expansion joint sealing section for the gap between two adjacent floor surfaces comprising an elastic bridging strip member having its two longitudinal edges secured to a rigid elongated intermediate member which in turn is secured to the vertical leg of an associated bracket which has a horizontal leg secured to the floor structure on each side of the gap. A cover strip is positioned over each of the longitudinal edges of the bridging strip and compressed there-against to form a watertight seal.