Tub Drain

The tub drain is the fitting assembly at the floor of a bathtub that collects water and directs it into the P-trap and drainpipe below. It typically includes a strainer (the visible screen in the tub floor), a stopper mechanism (for holding water during a bath), and a drain body that threads or snap-fits into the tub drain hole. The entire assembly connects to the P-trap through a drain shoe (a curved fitting that transitions from vertical to the horizontal trap).

What types of tub drain stoppers are there?

• Push-pull (most common): a knob on the stopper cap — push down to close, pull up to open. Simple and reliable; hair clogs at the stopper are cleared by unscrewing the cap and cleaning the stem.
• Lift-and-turn: twist the stopper cap to open or close. Similar in function to push-pull; can become difficult to operate as the set screw corrodes over time.
• Trip-lever (lever-operated): uses a plunger mechanism activated by a lever on the overflow plate. No stopper in the drain opening — the plunger blocks the drain inside the overflow tube. Effective but collects hair and requires more effort to clean.
• Toe-touch: press with your toe to open or close. Convenient, simple, but the ratchet mechanism can fail over time.
• Pop-up stopper: activated by the lift rod connected to the overflow plate, similar to sink pop-up drains.

How do you replace a tub drain body?

The drain body threads into the drain shoe in the floor of the tub. A drain key (cross-shaped tool) or a pair of pliers in the drain opening unscrews the old drain. Thread-sealing plumber's putty or silicone sealant is applied under the new drain flange before installation. Cost: $15–$50 for the assembly; $150–$350 for a plumber to replace a drain body and stopper.

What causes a slow tub drain?

Most slow tub drains are caused by hair and soap buildup at the stopper or in the P-trap below. Remove the stopper and pull out accumulated hair before calling a plumber. A drain cleaning tool (zip-it or drain stick) clears most simple tub drain clogs without chemicals.