Bathtub and shower drains: hair first, then what

A tub that holds an inch of water during a shower, or a shower pan that takes five minutes to empty, is the most common drain call there is. It is also the one a homeowner can usually handle in twenty minutes, because nine times out of ten the problem is a rope of hair sitting within reach of the drain opening. This guide covers getting to it, getting it out, and knowing when the drain is telling you something else.

Get the strainer or stopper out of the way

Shower drains usually have a flat strainer held by one or two screws, or a snap-in grate you lift with a flat screwdriver. Tub drains vary more, and the type decides how you remove it:

• Lift-and-turn or push-pull. Turn the cap counterclockwise while holding the body, or lift it and unscrew the knob, then the post underneath.
• Toe-touch. Hold the base and unscrew the cap, then the stem.
• Pop-up with a trip lever. The stopper in the drain is linked to a rocker arm. Open it and pull the stopper straight up; the arm comes with it.
• Trip lever with an internal plunger. The drain is open, no stopper, and a brass plunger inside the overflow tube moves up and down to block the line. Nothing to remove at the drain; the work is at the overflow plate.

Set the parts on a towel in the order they came off. Threads on old brass are soft, and forcing a stuck cap is how a stopper becomes a plumber visit.

Pull the hair

A plastic hair hook, the flexible strip with barbs sold at any hardware store, does the job. Push it down until it stops, twist, and pull. Expect to do it four or five times. Most of the mass is wrapped around the crossbars just inside the drain opening or around the stopper’s post, and a pair of needle-nose pliers reaches those. Clean the stopper itself; the underside is usually coated. Run hot water and see if it swirls straight down. If it does, you are done.

Clean the overflow and the trip-lever assembly

Water that goes down the overflow, and hair that goes with it, ends up in the same drain shoe below the tub. Remove the two screws on the overflow plate and pull the plate out gently. On a trip-lever tub the linkage and plunger come with it; on a pop-up tub the rocker linkage does. Both collect hair and soap where you cannot see it. Clean the linkage, and if the plunger is furred with scale from our hard water, soak it in vinegar. When you put it back, the drain should hold water with the lever down and empty with it up. If it does not, the linkage needs adjusting at its threaded rod, a quarter turn at a time.

Why chemical drain cleaners are the wrong move here

The bottle promises to dissolve hair. What it does in practice is generate heat and sit in the low spot of the trap, where the water stops it. In a home built before about 1975, that trap and the line after it are cast iron, already thinned by decades of use, and caustic cleaners eat the remaining wall. Under a tub, the drain shoe and the overflow tube are often chrome-plated brass, and the same chemicals pit them. Even on PVC, a cleaner that fails to clear the clog leaves a caustic pool for the next person who opens the drain. Hot water and a hook do the same job with none of that.

Keep it out of the drain

• A drain screen. A silicone or stainless hair catcher over the shower drain, or a mesh insert in a tub drain, stops most of the hair before it goes down. Empty it after each shower. This one habit ends most repeat clogs.
• Brush before the shower. Loose hair goes in the trash instead of the drain.
• A monthly hot flush. A kettle of hot, not boiling, water down a PVC tub drain keeps soap scum soft. Skip this on old cast iron and on acrylic tubs, where the heat does harm.

When it is the trap or the line, not the hair

This is where the drain stops being a twenty-minute job. If the hair is out and the tub still drains slowly, the clog is past the drain shoe, in the trap below the floor or in the branch line. On a slab home there is no access from below; the tub trap is encased in concrete, and the only way in is through the overflow with a small cable. A rented drum machine is too aggressive for a tub drain and can punch through old cast iron.

Other signs it is not the hair:

• Two fixtures are slow together, such as the tub and the bathroom sink, or the shower and the toilet. That is the branch line or the main.
• Gurgling from the tub when the toilet flushes or the washer drains.
• Water rising in the shower when nothing in that bathroom is running. That is a main line backup, and every fixture in the house should stop until it is cleared.
• Sewage smell from the drain that does not go away after the hair is out.

If the hair is out and the drain is still slow, or you have hit any of the signs above, send us a note with what you tried and which fixtures are affected. A small cable through the overflow clears most tub traps, and a camera tells us if the line under the slab is the real story.