A drain assembly includes a drain body and an expanding assembly. The drain body includes a first flange and a second flange that each extend away from an inner surface of the drain body towards a center of the drain body. The expanding assembly is positionable within the drain body between the first flange and the second flange. The expanding assembly includes a lattice body. The lattice body can be adjusted relative to the drain body such that the expanding assembly applies an axial force to the first flange and the second flange.