Quick answer
A slow shower or tub drain is usually hair and soap buildup in the stopper, strainer, or trap just below it. Remove the stopper, pull out the hair, and try a plastic hair tool or hand snake. Skip chemical openers. If several fixtures are slow, gurgle, or back up together, the problem is likely in the main line.
Why showers and tubs slow down
HomeTips lists hair, grease, and debris as the usual culprits when a single fixture drains slowly. In a shower or tub, hair and soap are the main ones. They collect on the stopper or strainer, then in the pipe just below it, and narrow the opening a little more with each use.
How many fixtures are affected is the most useful clue. HomeTips says that when only one fixture is slow, the clog is likely local. When several drains are slow, gurgling, or backing up, the cause is more likely the main drain or sewer line. Check that first, because it changes which fixes make sense.
Start with the stopper or strainer
Bob Vila's guide to unclogging a tub starts by removing the stopper, since that is where hair tends to gather. Stopper designs differ, so check what you have before pulling on anything.
- For a drop stopper, raise it fully, loosen the small screw on the shaft, and lift off the top.
- For a push or lock stopper, unscrew it and slide the shaft out.
- For a shower, lift or unscrew the drain cover and look underneath.
- Pull out the hair clump with a small hook or a flexible hair removal tool. Bob Vila describes bending a short length of wire into a hook for this.
- Bag the debris, run the water, and see if the drain is quick again.
A plastic hair tool, a hand snake, and prevention
If the stopper area is clean and the drain is still slow, go one step deeper. A plumbing company, Benjamin Franklin Plumbing, suggests trying a plastic hair snake first. You wear gloves, insert it, turn it slowly, and pull it out. Its barbs catch hair rather than breaking it up.
The same source describes a hand-crank sink auger as the next step. It reaches roughly two to three feet into the pipe to catch or push through a clog. Go slowly and do not force it. If the auger meets firm resistance or the problem seems deeper than it reaches, that points to something beyond a basic hair clog.
A hair catcher in the shower is the most effective habit. Benjamin Franklin Plumbing recommends emptying it after each shower, and Bob Vila suggests a drain cover for the tub. Bob Vila also says to avoid pouring mop water or other liquids with dirt, lint, or pet hair into the tub.
Hot water: helpful, but with a caution for plastic pipes
Bob Vila's guide suggests pouring in a quarter cup of liquid dish soap, then slowly following with hot water, as an option after the hair is out. It says to use only hot tap water on plastic pipes and to save boiling water for metal pipes.
Another source, a drain service company called Zoom Drain, explains why. It says PVC can soften or melt above the boiling point of water, and that hot water held in place by a clog could soften the pipe or loosen joints. It also says the water can push the clog farther down the line. If you do not know what your drain pipes are made of, skip boiling water.
Chemical drain openers: why many sources say to avoid them
Sources are not fully in agreement here. Benjamin Franklin Plumbing says bleach-based cleaners can work on an active clog but act slowly, and that enzyme cleaners are better as a monthly maintenance flush than for an existing clog. It also says baking soda and vinegar do not break down hair.
Safety is the bigger concern. Poison Control describes drain cleaners as strong alkalis. It says lye is very caustic and can cause severe eye injuries, including blindness, and that strong fumes can burn the lungs. It describes a case of a toddler splashed in the face when lye drain cleaner was poured into a sink. Its advice is never to mix household cleaning products, because the fumes can be poisonous.
HomeTips adds that chemical cleaners are usually ineffective on main line clogs and can damage pipes. There is another practical issue. A cleaner that sits in a standing pool can splash when you plunge or snake, and it is a hazard for whoever works on the drain next. If you have already used one, say so before anyone opens the drain.
When it points to the vent or main line
Drains need air to move water smoothly. HomeTips says that when several fixtures drain slowly at once, the system may not be balancing air pressure properly. Other signs of a blocked vent include toilets that gurgle when flushed, bubbling in nearby sinks or tubs, and toilet water levels that rise or fall unexpectedly.
Vent problems can also pull water out of traps. HomeTips explains that once a trap is emptied, sewer gas can pass through, and a trap that has lost its water is one source of drain odors. HomeTips suggests checking the roof vent for debris when several fixtures show these symptoms. Roof access is risky, and if clearing it does not help, the issue may be deeper.
HomeTips lists signs of a main sewer line clog: multiple slow drains, a gurgling toilet when other fixtures run, water backing up in a tub or shower, sewage odors, and standing water near floor drains. It adds that basement floor drains and tubs or showers are usually the first to back up because they sit lowest in the house.
If you suspect it, cut back on water. HomeTips advises avoiding sinks, showers, toilets, and the washing machine so the backup does not get worse. It says a drain auger may handle a minor clog, but deeper blockages usually call for professional tools.
One plumbing company, Benjamin Franklin Plumbing, suggests calling a plumber when a drain stays slow after snaking, when several drains are slow at once, when you hear gurgling, or when a clog returns within two weeks. That is one company's rule of thumb, not a standard.
When to call Pyper Plumbing
Call a plumber if the drain is still slow after you have cleaned the stopper and tried a hair tool, if the clog keeps coming back, if more than one fixture is affected, or if you smell sewage. Call right away if wastewater is coming up in a tub, shower, or floor drain.
Pyper Plumbing handles drain cleaning, sewer line repair, toilet repair, and emergency plumbing across Snohomish, Skagit, Whatcom, and Island counties. A plumber can tell you whether the issue is a local clog or the main line and will recommend the approach that fits. If you are on a septic system, Pyper does not do septic work, so a septic contractor is the right call.
Common questions
Why is my shower draining slowly?
The most common cause is hair, soap, and debris catching in the stopper, strainer, or the pipe just below. HomeTips says a single slow fixture is usually a local clog. If several drains are slow, suspect the main line.
Is it safe to pour boiling water down a shower drain?
Not if the pipes may be plastic. Zoom Drain says PVC can soften above water's boiling point, and Bob Vila's guide says to use only hot tap water on plastic pipes. If you are unsure what the pipes are, skip it.
Does baking soda and vinegar unclog a shower drain?
Benjamin Franklin Plumbing says it does not break down hair. Removing the hair with a tool is more reliable than relying on a reaction.
Why avoid chemical drain cleaners?
Poison Control describes strong alkali drain cleaners as very caustic, capable of burning skin, eyes, and lungs, and warns never to mix cleaning products. HomeTips also says they can damage pipes and are usually ineffective on main line clogs.
Sources
Facts in this guide come from the following references. Local rules and manufacturer instructions can differ, so follow your utility and your equipment manual.
- HomeTips: Drain and Sewer Problems
- HomeTips: Plumbing Vent Problems
- HomeTips: Sewer Line Clog Signs
- Bob Vila: How to Unclog a Bathtub
- Benjamin Franklin Plumbing: How Do I Unclog a Slow Shower?
- Zoom Drain: Will Pouring Boiling Water Down a Drain Unclog It?
- Poison Control: Spring Cleaning
This guide is general information, not a substitute for an on-site inspection. If you smell natural gas, leave the building and call 911 or your gas utility. Pyper does not perform gas line work.
