3 Reasons Your Bathroom Drain Is Slow (and Possible Solutions)

Updated March 4, 2022
Boy washing hands in bathroom sink
Photo: Imgorthand / Getty Images


  • Slow bathroom drains may indicate a larger plumbing issue.

  • A clogged pipe is often the reason for draining issues.

  • A plumbing snake, flushing with hot water, or gentle drain cleaner may help.

  • Slow drains may indicate pipe corrosion or intrusive tree roots.

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You’ve worked hard to turn your bathroom into the spa-like oasis of your dreams. But now you find yourself dozing off while waiting for your bathroom sink or tub to drain. But what’s really slowing down your bathroom plumbing and what can you do about it? Read on to learn how to identify the cause of your slow bathroom drain.

1. Clogged Drain

One of the most common reasons why your bathroom sinks are draining slowly could simply be that you have a clog. Fortunately, there are a few pretty simple options for clearing stopped-up drains and pipes. 

Simple tools such as a plunger or a handheld drain snake can help you clear the clog, especially if it’s relatively close to the drain. Tread gently, though, and avoid harshly pushing, pulling, or yanking. This cannot only cause the tool to get stuck or to break off inside your pipes, but it can also break or crack your pipes.

You can pour hot water or a store-bought liquid drain cleaner down your drains to dissolve debris and buildup and potentially remove clogs deeper within your system. Approach this strategy with caution, though, as some drain cleaners contain harsh chemicals that may damage your pipes. 

In general, drain cleaners that contain chemicals can be quite caustic and can eat away at your pipes over time, regardless of how new your plumbing is or what material it’s made of. If you use a store-bought drain cleaner, try to opt for those made from natural, non-corrosive, non-chemical ingredients. Bioenzymatic drain cleaners are usually the best natural drain cleaners that can be purchased over the counter and won’t threaten your pipes.

Using hot water to unclog a bathroom sink can be highly effective, especially in older homes with aging plumbing. But if the water is too hot (i.e. boiling), you may do more harm than good to your system.

2. Hair Buildup 

One of the leading causes of clogs in your bathroom drains and pipes is hair buildup. To keep hair in check, flush out your drains with hot water at least once a week and an enzymatic or bacteria-based drain cleaner once a month—or more if you have family members with particularly luxurious locks. 

These natural drain cleaners are non-corrosive and will not stress or eat away at your pipes. They also don’t produce harmful fumes or contact hazards, so you can use them regularly without risking either your plumbing or your family’s safety!

You should also clear hair away from drains each time you shower or bathe, and use a hair cap for shower and bathtub drains. If you lean over the sink to groom, be careful that no clippings get washed down the drain. Don’t forget to clean hair out of your sink stopper as well, but if it gets clogged you can fix a sink stopper with your DIY skills.

3. Maintenance Issues

Sometimes, it’s not a clog that is causing the problem but issues in the system itself. If you have an older home, for instance, your pipes may be corroding and breaking down, which can obstruct the flow of water and contribute to slow draining.

Likewise, if you have large trees near your home, root systems might have infiltrated your pipes, leading to blockages or breaks in the lines. A pro can perform a plumbing inspection, send a camera down the plumbing to diagnose any breaks, and recommend any necessary maintenance or repairs.

Call in a Professional

Plumber examining sink water flow
Photo: Peathegee Inc / Getty Images

If you’ve tried to clean and clear your drains and pipes and nothing is working, it may be time to call a local plumbing professional. Not only can a plumber clean out your drains effectively without risking damage to the system, but they can also inspect your plumbing and alert you to existing or potential problems. 

If you have a stubborn clog and you call in a pro, the cost to unclog a drain is between $150 and $350 on average. 

On the other hand, if you’re looking to maintain your system and prevent future issues by having your plumbing lines inspected and cleaned, you’re likely to pay around $150 per hour. Before you choose a drain cleaning service, though, you need to know what to look for, including the documentation you’ll need to ensure the service is reputable and effective.

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