Abstract: A method of manufacturing a prefabricated framed wall to be mounted in a floor of a building structure under construction has several steps: cutting at least one hole through all but one of a plurality of frame studs, a top frame plate, and a bottom frame plate; aligning the plurality of frame studs; securing tops of the frame studs to the top frame plate; securing bottoms of the frame studs to the bottom frame plate; installing plumbing and other pipes between the frame studs; and inserting at least one sanitary tee through the hole in the bottom frame plate so that it depends therebelow. The one sanitary tee connects below the floor to either a bathtub or a shower. An underfloor drain line is connected to at least one fixture, such as a bathtub/shower, a toilet and a lavatory. This underfloor drain line may be inserted either below the bottom frame plate outside the framed wall or near to but below the top frame plate inside the framed wall.

Abstract: A method of making a partition for a prefabricated framed wall to be mounted into a building structure under construction has several steps: cutting at least one hole through each of a plurality of frame studs, a top frame plate, and a bottom frame plate; aligning the plurality of frame studs; securing tops of the frame studs to the top frame plate; securing bottoms of the frame studs to the bottom frame plate; installing plumbing pipes between the frame studs; and inserting either a sanitary tee or a waste pipe connector or a heating/cooling duct through the holes in the bottom frame plate so that they depend therebelow. The sanitary tees connect below a bathroom floor to either a toilet fixture or a bathtub or a shower. The waste pipe connectors are connected below a floor to either a kitchen sink, a dishwasher, a laundry basin, or a clothes washer. The heating/cooling duct connects either below the bathroom floor or above the bathroom ceiling to either a heater or an air conditioner.