A shower that drains slowly is usually partly blocked by hair and soap scum near the strainer, but scale, a shared branch line or a blocked vent can slow it too. Time how long the water takes to clear, check whether other drains are slow, and clean the top of the drain by hand first. Our wider shower and tub drain guide lists every cause. This page is the quick diagnosis.
How do I tell why my shower is draining slowly?
Run the shower for one minute and note two things: how high the water rises around your feet, and whether it keeps rising or levels off. Then run a nearby sink and listen. The table below turns what you saw into a likely cause.
| What you see | Likely cause | First move |
|---|---|---|
| Water rises slowly, levels off, clears after a few minutes | Hair and scum at the strainer | Hook out the top of the drain |
| Slow from the first second, even with a clean cover | Partial clog in the trap | Cable through the strainer |
| Slow only after a long shower | Scale narrowing the pipe | Descale, then cable if needed |
| Sink or tub also slow | Shared branch line partly blocked | Cable from the sink or the cleanout |
| Gurgling or bubbling from other drains | Vent or main line problem | Stop and call |
| Slow, with a sewer smell | Dry trap or partly blocked line | Run water, then inspect |
Most showers fall in the first two rows. If yours matches the last three, the drain beyond the shower is the problem and hooking out hair will not help.
Why is my shower draining slow but not clogged?
A shower that is slow but not fully blocked has a restriction, not a plug. Hair and gel have narrowed the pipe, scale has crusted the walls, or a bend in the pipe is holding some water. The drain still works, which is why it looks fine when you test it with a cup.
The cup test misleads, because a shower puts out a lot more water than a cup. If the pipe can pass a slow trickle but not a steady stream, the water backs up.
One other possibility is worth checking. A vent that has lost airflow makes water glug through the trap instead of flowing, so the drain "feels clogged" even when the pipe is clean. If the shower is slow only when someone flushes a toilet or runs a washing machine, the shared line is overloaded or partly blocked.
How do I fix a slow draining shower step by step?
Start at the top of the drain and work down, because the cheapest fixes sit there and most slow showers respond to them. Each step takes only a few minutes and costs almost nothing. Stop as soon as the water clears, and note which step made the difference.
- Lift the cover and remove hair with a bent wire or plastic strip.
- Wipe the drain body and soak the cover in white vinegar if it has scale.
- Run hot tap water for a minute and time the drop.
- Feed a 1/4 inch hand auger through the opening and clear the trap.
- Run water again. If the drain is still slow, move to the next section.
A fine mesh hair catcher over the drain afterwards stops it returning. Our page on cleaning hair from a drain compares the tools, and cleaning out a shower drain goes through each cover type and the snaking sequence.
Skip the chemical bottle until you have tried the hook and the cable. Drain cleaners are strong alkalis that can burn skin and lungs, and you should not combine cleaning products.
Does hard water make a shower drain slow?
It can. Hard water leaves soap scum, which Wikipedia describes as a lime soap formed when soap meets calcium and magnesium. Over months it coats the inside of the pipe and the strainer, so the pipe gets narrower and hair has more to grab.
LADWP says hardness varies across Los Angeles. Its 2022 figures give an average of 8.6 grains per gallon for the San Fernando Valley and western Los Angeles, 9.8 for Silver Lake, Downtown and South Los Angeles, and 16.3 for eastern Los Angeles and the Harbor. Your own water report will show which supply you are on.
In harder areas, a monthly vinegar soak of the strainer and a good flush help. A water softener can reduce the scale, but it is a bigger decision, and it will not remove hair. Scale usually slows a shower over months. A sudden slowdown points elsewhere.
When is a slow shower drain a sign of a bigger problem?
When more than one fixture is slow, when you hear gurgling from other drains, when water backs into the tub as the shower runs, or when the slowness returns within days of a proper cable run. Those patterns mean the branch line or the main line is partly blocked.
LA Sanitation attributes over half of sewer backups to roots and poured grease. Roots often grow into joints in older lateral lines, and kitchen grease can travel into a shared branch. You cannot see either from the bathroom, so a camera is the way to look.
If a smell comes with the slowness, run water into the shower for a minute. A dry trap loses its water seal and lets gas through, which Wikipedia notes is why the seal matters. If the smell stays, the pipe or the vent needs inspection. Our sewer camera inspection page explains the visit.
Can I fix this myself or should I book a visit?
You can fix most top-of-drain slowdowns yourself in about 15 minutes with a hook and a hand cable. Book a visit when the cable does not help, when the shower is slow again within a few days, or when the problem shows up in several fixtures at once.
A local drain cleaner can visit, clear the line and put the price in writing before starting. A shower with a plain blockage is a short visit, and ranges are on our drain cleaning cost page. If you want to compare options, send a price request and tell us what the drain does now. The LA Drain Works home page lists the other jobs we arrange.
Questions people ask
Why is my shower draining slow all of a sudden?
A sudden slowdown usually means a clump of hair or a bar of soap sliver has moved into the trap. It can also mean a shared branch line has partly blocked. Check the strainer first, then try a cable. If other drains are slow too, the problem is further down.
How long should a shower take to drain?
Water should drain as fast as it arrives, with only a thin film around your feet. If it pools above your ankles within a minute and takes more than a couple of minutes to clear after you turn the shower off, the drain is slower than it should be.
Will baking soda and vinegar fix a slow shower drain?
It freshens a lightly coated pipe, but it does not remove a hair mat or heavy scale. Use it after you have hooked out the hair, then rinse with hot tap water. If the drain is still slow after that, a cable is the better next step.
What should I ask before booking a slow shower repair?
Ask if a camera comes along when the cable does not help, whether the quote covers the trap and the branch line, and whether the price is written before work starts. If the shower slows again in a week, ask who returns and at what cost.
Do I have to stay home for the visit?
An adult should let the visitor in and say which shower is slow and how it behaves. Clear the floor and move any mats. Staying in the room is not required, but you will want to be nearby to describe the pattern you saw.
Sources used
Page updated