Use a drill driver to unscrew the vanity top from the vanity cabinet.
How to remove a bathroom vanity with floor plumbing.
Cut out the floor of the vanity using a reciprocating saw.
Depending on the size of the holes cut in the bottom of the old vanity you may need to take the valves off the pipes to remove the vanity.
Remove all screws with a drill or screwdriver.
Remove the fixtures and disconnect the water feeds and drains.
Remove any trim where the cabinet meets the walls if applicable.
You remove your trap and all stop valves back to a point where you just have 3 pipes coming straight up through the floor.
Take careful measurements of the 3 pipes and their location compared to the back wall and transfer these measurements to the floor of the vanity.
Check inside the cabinet to determine where it is attached to the wall.
Measure and cut holes through the bottom shelf using a 1 1 4 inch spade bit and drill driver.
Turning off the water you will need to turn off the water source to the sink of the bathroom.
You can crimp copper tubing or purchase special caps for pvc tubes.
Do not rely on.
Remove the vanity cabinet.
Shut off the water to the bathroom.
If the cabinet is attached with nails carefully pry it away from the wall with a flat pry bar.
Pick up the vanity and place it over the holes.
I d make a cardboard template to test out my accuracy.
This style of sink can take up very little space while also providing an unusual feature and focal point in the bathroom.
Some older homes have only a meter shut off outside.
Without a vanity your plumbing will be visible.
Cut one hole for each valve emerging from the floor.
Cap and seal all old water feeds.
Installation of this type of thinking is more difficult and will cost.
Turn off the water supply before you begin this is usually located in a utility room.