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How to Fix a Slow-Draining Bathtub: Six Methods

Since leaving college, Paul has worked in a variety of roles, including: painter and decorator, general handyman, and freelance writer.

A slow-draining bathtub is annoying and just gets worse if not dealt with. Find out what to do when dirt, hair, and soap blocks the drainage.

A slow-draining bathtub is annoying and just gets worse if not dealt with. Find out what to do when dirt, hair, and soap blocks the drainage.

In my experience, it's always worth trying to avoid the expense of hiring a plumber if you can help it. Fixing a slow-draining bathtub yourself often isn’t anywhere near as hard as many people think. Most clogged bath drain issues can be resolved by using some easy, affordable, and straightforward tools and methods.

Once you have fixed the bathtub drain, you should work on preventing or reducing the chances of it happening again—see my suggestions at the bottom of the page.

Six Ways to Fix a Slow-Draining Bathtub

  1. Use baking soda and vinegar (the natural alternative to chemicals).
  2. Use a plunger.
  3. Use a commercial (chemical) clog remover.
  4. Remove the drain stopper to inspect and gain access.
  5. Use a plumbers’ snake.
  6. Call a plumber.

I will go into each of the above methods in detail below. Generally speaking, the list starts with the easier, less-involved, and cheaper methods and progresses to more-involved and expensive methods. So if in doubt, start with #1 and work your way down the list.

In my experience, clearing a clogged bathtub drain can often requires a combination of more than one of these methods.

Before You Begin. . .

Plumbing is messy work. Put on some old clothes before you start. You may want to put down some old towels around the work area to soak up any water that spills. Stagnant water is unsanitary, so a pair of rubber gloves will protect your hands from germs.

1. Baking Soda and Vinegar

A more natural solution than using cleaning chemicals, this method will clear moderate blockages.

How to Unclog a Bathtub Drain Using Baking Soda and Vinegar

  1. Pour a half cup of baking soda down the drain opening.
  2. Follow that with a cup of white vinegar.
  3. Let the combined ingredients foam for five minutes.
  4. Run the hot water for a minute or so.
  5. Examine the bathtub drainage to determine if it still is slow.

Note:The two main advantages of this method are that it is ecologically preferable and won't cause damage to plastic pipes. It is not so effective on serious blockages, however, and you may still end up having to resort to chemicals. For other natural remedies, read about 5 Homemade Drain Cleaners for Clogged Drains.

Try using a plunger to dislodge the clog and clear the blockage.

Try using a plunger to dislodge the clog and clear the blockage.

2. Use a Plunger

As a method, plunging is always worth a try, as the time and costs involved are relatively small. Plunging can be successful, though it depends on the nature of the blockage, the location of the clog, and the design of your drain. The plunger uses suction to work, so if the clog is deep and made of mainly hair, for instance, this method may not be effective.

How to Unclog Your Bathtub Drain Using a Plunger

  1. Add petroleum jelly to the rim of the plunger to get a better seal.
  2. Add enough water to the bathtub so that the head of the plunger is submerged.
  3. Plunge the bathtub drain opening by pumping vigorously.

Note: If using one plunger doesn't work, try using the two plunger method: Put one plunger over the overflow panel, so that the cup seals it off and hopefully gives you better suction, and simultaneously plunge the drain opening with the other plunger.

3. Commercial (Chemical) Clog Remover

Widely available at hardware stores and supermarkets, strong chemical cleaners are designed to unblock drains. Follow the instructions on the label or box carefully.

How to Unclog a Shower Drain Using Chemicals

  • Read and follow the directions on the packaging, including the correct amount of the product to use. The amount you use will vary.
  • Use gloves and goggles to protect your hands and eyes.
  • Don't combine different chemicals, as this can create poisonous gas.
  • Pour chemicals down the drain opening.

Note: Chemicals should not be treated lightly. They can cause damage to your drainage pipes, especially if used repeatedly. Using chemicals is typically a fast, straightforward, and affordable method with a fairly high success rate in my experience. You can reduce the need for chemicals, however, by minimizing future blockages occurring (see the bottom of page)!

Chemical Products Used to Fix Slow Drainage

ProductPriceOnline RatingPoisonous

Rooto Professional Drain Opener

$10

4 stars

Yes

Instant Power Hair & Grease Drain Opener

$10

4 stars

Yes

Drainbo Drain Cleaner

$10

3.5 stars

Yes

Unique Super Digest-It Safe Drain Opener

$13

5 stars

No, but it will still make you ill if you drink it.

Clean Earth Earthworm Family Safe Drain Cleaner

$6

3.5 stars

No, but it will still make you ill if you drink it.

4. Remove the Drain Stopper to Inspect and Gain Access

If you've tried the above methods and none of them have worked, it's time to get down and dirty. You need to unscrew and take off the overflow plate, then remove the stopper.

The stopper works by lifting and dropping a plunger to open and close the drain. It is operated by a small lever. If the stopper is not working correctly, it might be stuck in a semi-closed position, restricting water flow. The positioning of the plunger can be easily adjusted with the lock nuts that hold the plunger to the threaded rod.

If the stopper works okay, then your problem is likely to be a clog, and you will need to use a plumbers' snake. You can use the overflow for access.

Note: Hair and soap can often accumulate underneath the drainage strainer, too, so I recommend removing that for inspection and access. Some strainers can be removed manually, while others have screws that need to be removed first.

5. Use a Plumbers’ Snake

This is another inexpensive method for fixing a slow bathtub drain. The success rate is high if the issue your dealing with is a clog.

How to Unclog Your Bathtub Drain Using a Plumbers' Snake

  1. You can gain access to the drain via the overflow, once you've removed the stopper (see above). An alternative route is via the drain opening, after you've removed the strainer. Feed the snake down until the clog is reached.
  2. Turn the handle to bring the snake back up.
  3. Run water to check the drain and make sure that the clog is completely gone.
  4. You may need to repeat this process several times.

Note: Clogs caused by invasive roots will require more than a plumbers' snake to fix. If you need more help, read more about how to use a plumbing snake.

6. Call a Plumber

If you are unwilling to take your drain apart and don't feel comfortable with using chemicals (or they simply don't work), then you will have to call a professional plumber. It’s obviously the last resort if you are looking to save money. That said, it is also the least trouble.

What Causes a Tub to Drain Slowly?

Typically the cause of a slow-draining bathtub is a clog that is restricting water flow. Clogs are usually made up of knotted hair, dirt, grease, and/or soap. They can be difficult to remove because hair can wrap around parts of the drain.

Clogs happen more frequently in homes where inhabitants have long hair, as short hair is much less likely to get caught in the drain system.

Causes of Clogs in Bathtub Drains

CauseHow It Happens

Hair

Hair can combine with soap and dirt and clump together to form clogs. It can also attach to drains and pipes, making it difficult to remove.

Soap

Traditional soap bars are made with grease or fat. The fat combines with minerals in water and leaves a hard residue that clogs pipes. Soap can also combine with hair and dirt.

Dirt

Dirt can build up and cause problems. The very nature of bathing means that we are constantly sending dirt down the drain.

Stopper

If the stopper hasn't been fitted correctly or is out of position, it may become stuck in a semi-closed position, and the plunger may restrict drainage.

Tree roots

Older underground pipes can crack or leak, attracting root growth. Once inside your pipes, roots grow larger, blocking water flow and causing pipe damage.

Mineral build up

Minerals dissolved in water can build up over time and create insoluble masses that will block your drains.

Symptoms of a Slow-Draining Tub

"Slow draining" means that the water stays in the tub for far longer than it should after you have pulled the plug. The water either takes longer than it should to disappear or, in more serious cases, it remains indefinitely. The problem can develop gradually and may not be immediately noticeable. It's common for people to disregard the issue until it has become too serious to ignore.

Unfortunately, once the drainage problems have begun, they will usually only get worse unless action is taken. This is because clogs tend to gather and accumulate more debris (such as hair, dirt, and soap) over time and become bigger and more firmly fixed. The sooner that you deal with the problem, the easier it will be to resolve.

How to Prevent a Bathtub From Slow-Draining

Prevention is almost always better than cure, of course. So once your drainage problems are resolved, don't forget to minimize the possibility of your bathtub drain getting clogged again. Below are two things to try.

  • Firstly, you should certainly think about buying a good drain protector, if you don't already have one, to prevent hair, children's toys, plus other small items and debris from entering the drain.
  • Secondly, a secure soap dish can often help, as soap contributes to clogs forming by binding knots of hair together into larger clumps. (Soap falling into the tub or onto the floor can also cause serious accidents due to people slipping.)

Is There a Good Drain Protector That You Can Recommend for a Bathtub?

There are lots of great products out there that will do the job effectively. Bear in mind that there are different types of drain stoppers and the screen you buy will have to take this into account. Common types of bathtub drain stopper include:

  • Push-and-pull
  • Lift-and-turn
  • Toe-touch
  • Pop-up
  • Flip-it
  • Trip lever

If you want me to make a general suggestion for a protector that works with the majority of bathtub drains, I would recommend the OXO Good Grips, which provide a great barrier for catching small debris without slowing down water drainage and work with both pop-up and regular drains. The OXO Good Grip is better than most of its rivals as it has a bit of weight to it and so doesn't have the tendency to float up and away like some of the cheaper protectors do. It's also affordable and easy to clean.

The other bathtub drain protector that I am a particular fan of is the Tubshroom. This protector fits inside the drain rather than sitting on top and is particularly good at catching hair. If your tub is the type where you flip a switch for drainage, then you can just leave the Tubshroom in place. If it's the type that has a removable stopper, then you put the Tubshroom in when the tub is draining. Some people complain that it is awkward to clean, but I've not had much trouble.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2018 Paul Goodman

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