Abstract: A shower base assembly includes a shower base, a drain grate frame, a double-threaded flange nipple, and a rubber gasket. The shower base includes a upper side pre-sloped to allow for water drainage to drain hole extending to a lower side of the shower base. The drain grate frame is insertable through the drain hole from the shower base upper side to be received within the double-threaded flange nipple. An industry standard plumbing drain body may engage the double-threaded flange nipple from the shower base lower side. The rubber gasket is compressed against the shower base about the drain hole between the double-threaded flange nipple and the drain body.

Abstract: A structural, shower base assembly is provided. The assembly includes a tile-over shower base pan, a tile drain grate frame, a double threaded flange nipple, and a rubber gasket. The tile-over shower base pan includes a dorsal side pre-sloped to allow for consistent water draining to a dorsal opening of a centered drain hole of the tile-over shower base pan, and a ventral side having a ventral opening of the centered drain hole of the tile-over shower base pan and a reinforcement ring. The tile drain grate frame is compatible with the dorsal opening and the ventral opening. The double threaded flange nipple is compatible with the tile drain grate frame and an industry standard plumbing drain body. The rubber gasket is compressed to the reinforcement ring to seal a connection between the double threaded flange nipple and the industry standard plumbing drain body.