Shut off the water at the main. Turn the water heater to "off," or turn the switch to the "pilot" position if it's gas. Drain the plumbing by opening a faucet. Remove the old sink and trap.
Take off the old lavatory stops. The plumbing for a pedestal sink is exposed, so all of the plumbing, including the stops need to be new. It will also be necessary to install a new chrome lavatory stop and escutcheon cover.
Using two adjustable wrenches, remove the old supply stops from the hot and cold water lines (Image 1), and then remove the old escutcheon covers (escutcheon: decorative metal shield that covers the faucet stem and the hole in the wall).
Apply Teflon tape on both stub outs, and then add new escutcheon covers by sliding the cover over the roughed in water supply.
Thread new supply stops on both (Image 2) and use a wrench to tighten everything up. Ensure that the inlet valve is in the upright position.
Unscrew the old collar nut, and then slide the new p-trap escutcheon cover over the drain hole.
Place the lavatory on the pedestal, and then set it in the desired location. Make sure the lavatory is level (Image 1).
Be sure to center the pedestal to the drain hole on the wall. Once the pedestal is centered, use a pencil to mark where the sink will sit against the wall (Image 2).
Use a pencil to mark where the anchor holes will be drilled in the wall and floor. After the holes have been marked, remove the sink from the area. Install the lag screws into the wood backing behind the wall. Ensure your bit is at least a size smaller than the lag bolts so they'll hold tight in the wall.
Drill two 1/4" holes for the hanger bolts at the marks on the wall. Thread the hanger bolts into the wall. Leave approximately 1-1/4" of each bolt exposed between the cap nuts and the finished wall.
The pedestal sink must be mounted to the floor for stability. The technique for doing this will vary depending on the type of floor.
Note: Don't apply sealant around the base of the pedestal. It could damage the floor if the sink ever needs to be moved.
"Dressing" the sink means to put all of the hardware on the sink before installation (Image 1)
Install the spout and handles (Image 2) Use a roll of plumber's putty around the seal to make sure it's water tight. Insert the valve bodies into the proper mounting holes, ensuring that the valve body marked "cold" is installed to the right of the center hole. Once the valve body is in place, slide the metal washer and nut onto the base, and then tighten it down.
Place the seal ring over the spout body, and then insert the spout into the sink. Place the metal washer and nut onto the spout shank and tighten the nut with a wrench.
Install the hot water valve the same way as the cold water valve. Don't forget to use plumber's putty.
With the hardware mounted on the topside of the sink, mount the supply lines underneath the sink.
Screw the supply tee to the bottom of the spout, and then tighten it up with a pair of slip joint pliers (Image 1).
Attach the flexible supply lines to the hot and cold valve bodies, and then attach them to the supply tee. Connect both the hot and cold flexible supply lines to each of the valve bodies, tightening each one with a wrench (Image 2).
Apply a generous amount of plumber's putty around the base of the flange, and then place the flange in the sink.
Place the nylon o-ring and nut over the flange. Tighten with slip-joint pliers. Attach the drain body to the flange, ensuring a tight seal (Image 1).
Use Teflon tape around the threads of the tailpiece to prevent the drain assembly from leaking.
Screw the tailpiece to the drain body. Attach the connecting rod to the drain body, and then connect the stopper rod from the back of the faucet to complete the drain assembly (Image 2).
Set the lavatory on the pedestal so that the hanger bolts extend through the lavatory holes. Install the cap nuts and washers, and then tighten.
With the sink mounted, connect both the hot and cold water connections. Tighten with slip-joint pliers.
Secure the end of the p-trap to the tailpiece of the drain assembly. Connect the p-trap to the tailpiece by screwing it into place using the threaded connection.
Turn the water on at the main. Turn on the water heater. Open the faucet at the new sink, and then check for leaks.