How to Unclog a Bathtub Full of Water

A bathtub drain is connected to the other house fixtures drains (toilet, sink etc.) further down in the main house plumbing system.

Just like the other fixtures, a bathtub drain is fitted with a U-shaped trap that holds all the potential clogs, preventing them from forming clogs further down the drainpipe which is usually harder to unclog.

A clogged bathtub drain is mainly caused by hair, soap scum, mineral deposits or a drain stopper that is not properly adjusted. A single or combination of these factors will cause a slow draining bathtub or a fully clogged one.

To unclog a bathtub with standing water, you will first need to drain away the water. Attempting to plunge or snake a full bathtub will be very difficult and messy.

There are several methods of unclogging a slow draining or bathtub full of water. You should aim to start with the easiest one and upgrade steadily to the most technical one.

Here is how to unclog a bathtub with standing water:

Drain the bathtub
Plunge the bathtub
Pour a baking soda and vinegar solution
Dump boiling water down the drain
Snake the bathtub
Call a plumber if unsuccessful

Before unclogging a bathtub, it is important to ensure that only the bathtub is clogged and not any other fixture. If the clog is affecting more than just one fixture you will notice the bathtub drain gurgling or backing up when the toilet is flushed.

Step 1: Drain the Bathtub

There is no an easy way to drain a bathtub other than scooping the water and dumping it elsewhere. Put on some rubbers gloves and get down to business.

It is very important that you put some towels/rags/cartons on the bathroom floor especially if it is tiled as water can make it very slippery, which can cause serious falls.

Pick up a bucket/pail and scoop water from the tub dumping it down the toilet bowl. I am sure there are other methods but this is the fastest one.
Use a sponge to completely dry the inside of the tub since you will at some point need to work from the inside.

Step 2: Plunge the Bathtub

Plunging is one of the fastest ways of unclogging a bathtub. In most of the times this will be enough to completely clear the drain. It works by creating a pressure differential between the top and bottom of the clog forcing it to be dislodged.

Here is how to unclog a bathtub using a plunger:

Remove the bathtub stopper. Depending on the type of bathtub you have, the stopper will most likely be located on the top of the drain or on the overflow plate.
For those located on top of the drain, some will only need to be lifted off while others are threaded and you must turn them counterclockwise to remove them. If you have a pop-up stopper look for a screw under the cover and loosen (no need to remove it completely) it with a screwdriver then lift it off.
A trip lever tub stopper is the one located on the overflow plate. Remove the screws and pull it out.

With the bathtub stopper out, try to see if you can see any hair or soap scup down the drain. If that is the case, take a coat hanger, straighten it and make a hook at the front. Use the hook to remove as much hair as possible.

Blast hot how into the tub and see if there is any change. If there is no change go ahead and plunge the tub.

Cover the tub drain with the plunger and add water inside the tub until the base of the plunger is covered with water all round.
To help create a vacuum, plug off the outflow (usually covered with a plate. Remove the plate with a screw driver) with a towel/rag. If you have another plunger you can use it instead of the towel. Cover the tub outflow and have someone hold it in place tightly.
Start to plunge the bathtub drain starting off gently and then aggressively.
Lift off the plunger and check if the tub is draining.

If this method does not work out move on to the next one.

Step 3: Try Baking Soda and Vinegar

Although you can use both baking soda and vinegar independently, using them together works even better. Baking soda is an alkaline while white vinegar is a mild acidic.

These 2 substances produce a fizzing reaction that is very effective in eating away the grime, dissolving soap scup and mineral deposits. To make sure that the solution is working directly on the clog, you will again need to remove all the water from the bathtub.

Pour 1 cup of baking soda down the bathtub drain.
Add 1 cup of white vinegar slowly. Remember when vinegar and baking soda are mixed, foam and bubbles are formed which can rise up sharply and hence the need to pour the vinegar slowly.
Give the solution 5 minutes to work out its magic.
While that is happening, boil 1 big pot of water and pour it down the bathtub drain. Hot water is every effective in melting soap and will surely work with the baking soda and vinegar solution in unclogging the bathtub.

If this method still doesn’t work, you will need to upgrade to a more effective tool. The plumber’s snake/auger.

Step 4: Bring on the Plumber’s Snake

A plumber’s snake, also known as an auger is a long cable rolled in a drum with a hooked head and cranking handle that unclogs drain by either hooking and out the clogs or breaking them it into smaller pieces.

Unlike a toilet, snaking a bathtub is very easy. You just need to be careful that the auger’s head does not scratch the inside of the bathtub.

To snake a bathtub, you can either feed the auger through the bathtub drain or the overflow outlet. The overflow outlet is in my opinion the most effective.

Pull out the cable and push it down the tub overflow until you come across a restriction. Tighten the cable in place using the drum screw.
Pushing hard against the restriction, start turning the handle clockwise until you go through it.
Release a few more inches of the cable from the drum, screw it in place and repeat the above process.
You might need to do this a few more times with different cable sizes to make sure that you have removed everything.
To avoid scratching the tub, bring the drum near the out flow and push the cable back into the drum slowly. Pulling the cable all out at once would have it swinging inside the tub leaving ugly marks everywhere its head comes into contact with.

Check if your bathtub is draining as it should. Most of the time this method will be enough to unclog even a badly clogged bathtub.

Step 5: Use a Shop Vac

If you have tried plunging, snaking and all the above methods without success, there is still one more thing you can do that works really well and fast. A shop vac!

It may sound a little crazy but it works like a charm. The best thing is that you don’t even have to drain the bathtub. So head to your garage and bring the shop vac to the bathroom.

Prior to starting the shop vac, remember to plug off the tub outflow. This will help you get an even stronger suction.
Now place the shop vac pipe on top of the bathtub drain and press down tightly. If it is smaller use a rag to hold it in place.
Start the shop vac and let it run for a few seconds. Lift off the pipe and check if the tub is drain. You might need to do this a few times to suck out everything.
Once done don’t forget to clean the shop vac.

Should You Use Chemical Drain Cleaners?

There are lots of chemicals that can be used to unclog a bathtub and other drains. Should you use them though? The simple answer is no. Their disadvantages outweigh their advantages by far.

To start with, these chemicals emit a lot of heat which softens and finally breaks downs pipes. While they may successfully unclog the bathtub, the cost of replacing the drainpipe is quite high and therefore not worth it.

This chemicals are also quite bad for the environment. If everyone in the United States decided to use chemicals to unclog their drains you can imagine the amount of it that would finally end up at the municipal water and later out in the environment.

Finally chemicals should especially not be used to unclog bathtub or any other drains by people on septic systems. These chemicals kill all the good bacteria inside the septic tank, which will also be very costly to fix.

Summary

To unclog a bathtub full of water, follow these steps:

Safety First: Ensure you have a safe and slip-resistant surface to work on. Be cautious when dealing with water and chemicals to avoid accidents.
Remove Excess Water: If the water level is dangerously high, use a bucket or container to remove some water from the tub. This will make it easier to work on the clog.
Check the Drain Stopper: Remove the drain stopper or cover and inspect it for any hair or debris that may be obstructing the drain. Clean and reinsert it properly.
Use a Plunger:
- Place a plunger over the drain.
- Fill the tub with enough water to cover the plunger’s cup.
- Push and pull the plunger vigorously to create a suction force. This can help dislodge the clog.
Try a Drain Snake or Auger: If the plunger doesn’t work, use a drain snake or auger. Insert it into the drain and turn the handle clockwise while applying gentle pressure. Rotate the snake to break up or pull out the clog.
Chemical Drain Cleaners (Optional): As a last resort, you can use a chemical drain cleaner, following the manufacturer’s instructions carefully. Be cautious when using chemicals, as they can be harmful to you, your plumbing, and the environment.
Flush with Hot Water: After removing the clog, flush the drain with hot water to help clear any remaining debris and ensure the water flows smoothly.
Prevent Future Clogs: Consider using a drain cover or hair catcher to prevent hair and debris from going down the drain in the future.

Related post: How to fix a slow draining bathtub