We are considering buying a house that has one sink in the master bathroom. We never use a tub so we are considering removing the tub and adding an extra sink. Is there a difference in a sink drain and a tub drain? Can a sink be drained where a tub was set up?

There is a size difference but you can drain a sink to a bath drain. Unless you have open access from below you will need to open the floor to remove the tubs trap before you install a reducer to accept the 1 1/4" sink drain. However, ask a real estate agent what this customization does to your home value. Isn't there some way to install a double sink where the single currently sits? Some Tricks to Include a Small Double Sink Vanity For Tight Spaces

Hi all:

The tub drain and most lavatory drains are usually piped up 1.5". You'll want to cap off the tub drain just below the floor level (remove old tub waste entirely) and then install an 1.5" sanitary tee fitting into the tub vent at about 18" off the finish floor to connect a lavatory.

You'll want to reduce that 1.5" sanitary tee to 1.25" after the pipe enters the vanity cabinet... can be done a number of ways depending on the lavatory/vanity chosen.

Let us know if you intend to install a pedestal or a vanity base/top... confirm the numbers quickly!

Mark