How to Change a Plastic Valve to Metal in the Bathroom

Turn off the main water supply valves to the lines that supply water to your home. Open a kitchen faucet to allow water to drain out of the supply lines.

Place shop towels on the floor to prevent water from dripping on the floor. Disconnect the water supply line from the valve to your toilet or sink by turning the valve nut counterclockwise with an adjustable wrench.

Turn the plastic valve counterclockwise, with an adjustable wrench, to unthread it from the supply line fitting running from the main water supply.

Wrap a layer of plumber's tape around the threads of the new metal valve. Insert the valve into the threaded receptacle of the line running from your home's main water supply. Turn the new valve clockwise and tighten it with an adjustable wrench.

Wrap plumber's tape around the threads of the valve that connect to the supply line running to the toilet or sink. Place the supply line nut over the threads and tighten the nut with an adjustable wrench.

Turn on the main water supply valves, and turn on the new valve to supply water to your bathroom fixture. Flush the toilet or turn on the sink faucet to ensure that it works properly. Check the valve for leaks.