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How To Install A Bathtub Overflow Drain? [8 Simple Steps]

The bathtub overflow drain is a crucial component of your tub. By capturing overflowing water, it keeps the tub from overflowing. And the water is diverted into the drain system using this. 

Now installing this can sound complicated to many. Don’t worry, we’ve got your back for this!

How to install a bathtub overflow drain?

To install a bathtub overflow drain,  you need to detach the drain fittings first. Then remove the cover plate and the overflow itself. The next step is to test fit and attach the overflow assembly. Then connect the drain fittings and attach the cover plate. Finally, inspect the installation after you’re done.

This is just the beginning of what you’re looking for. Manage some time to get into the details!

Sounds about right? Read along!

How To Install A Bathtub Overflow Drain? 8 Doable Steps

An overflow drain is quite necessary for the bathtub. You may ask professionals to do this. But you may also do it yourself. You can save a hefty amount by doing it yourself. 

We’ve segmented the process into 8 simple steps. You could do this easily following our guide.

Tools Required

Before we go into the installation process, get ready with the required tools. Let’s see the tools you need for this-

  • Screwdrivers
  • Plumber’s putty
  • Channel-lock pliers
  • Tub drain wrench
  • Bathtub drain and overflow kit 

Got the tools? Now let’s get to work!

Step 1: Detach The Drain Fitting

Remove the drain fitting from the tub’s bottom first. To obtain access to the drain body, you may need to detach the cover grid. 

Then take a drain wrench to grip the drain fitting. By rotating counterclockwise, loosen it from the drain arm.

Make sure to use a strong wrench for this job. Here are some of our suggestions in case you need one-

Product 1
Product 2

These are wrenches that are quite flexible, strong, and durable.

Step 2: Remove The Connection Of Overflow Cover Plate

Now, unscrew the overflow cover plate, which is located on the front wall of the bathtub. This may require removing one or two screws. Then remove the cover plate now. 

Sometimes if there is a rubber washer, it becomes hard to remove the plate. In that case, put more force and the cover plate will be removed gradually.

Step 3: Remove The Overflow

Now, remove the waste-and-overflow stuff from beneath the tub. And disconnect it from the drain pipes. It’s sometimes as simple as releasing the drain pipes’ slide nuts. 

The pipes might have been soldered in place. In that case, cutting them loose with a hacksaw or tubing cutter may be necessary. Before you make any cuts, think about it. The redesigned waste-and-overflow tube will be easy to install with careful cutting.

Step 4: Test Fit The Overflow Assembly

Before disconnecting the overflow kit components, you must turn off the water valve. But make sure not to be rough, or else the handle might break off!

Remove the overflow kit’s components and test-fit them on your tub. If the kit doesn’t perfectly suit the measurements of your tub, you might need to cut a bit. Having someone inside the tub to hold items while you line everything up makes things easier.

Dry-fit the pieces once more after cutting. This will ensure that the overflow tube and drain arm are properly aligned. It’s simple to set up a waste-and-overflow system with slip-joints. 

Because you can slide everything into place while leaving the washers and nuts unfastened. You can use extensions on the 1 1/2-inch tubular tubing if necessary. Doing so would lengthen the overflow tube.

Step 5: Attach The Overflow Assembly

Place the assembly in its final position. So that the top of the overflow tube lines up with the bathtub’s overflow opening. The horizontal drain arm is also aligned with the drain aperture on the bathtub’s bottom.

You may only need to slip fittings to make the connections. It mainly depends on the sort of kit you’re using. It may also be necessary to permanently solder the PVC seams with solvent adhesive. 

At this point, secure the slip nuts if you’re using slip joints to make the connections. But you can also try connecting the pipes without glue if you wish. 

Step 6: Drain Fitting Connection

Now, you need to attach the fittings of the drain. Begin by applying a bead of plumber’s putty to the flange of the drain opening. Wrap the rubber washer around the drain tailpiece that is threaded from beneath the tub. 

Then slid up the tailpiece through the drain aperture. Thread the drain fitting into the threaded tailpiece of the drain arm. Then use a drain wrench to tighten it up. 

It’s easiest if you have someone below the tub to hold the drain arm in place. As you tighten the drain fitting, the plumber’s putty should gently leak out around the flange.

Step 7: Attach The Cover Plate Of The Overflow 

Now, place the overflow tube’s gasket on the tub’s rear. Then position between the bathtub wall and the overflow tube’s mouth. The gasket’s thicker side would face down if the gasket is tapered. 

Place the cover plate on top of the overflow opening from within the tub. And fasten it in place with mounting screws that thread into the overflow tube’s screw apertures. If you can’t do it properly, the cover plate screws might get rusted.

Securely tighten the screws. Between the mouth of the overflow tube and the tub backside, the gasket should compress somewhat.

Step 8: Inspect The Installation

Swipe any surplus putty surrounding the flange of the drain fitting. While you’re watching, have your assistant run water down the tub drain. This ensures to leave no leaks beneath the tub. 

Fill the tub with a minimum of 4 inches of water and close the tub stopper. Allow it to drain quickly after that to provide a proper volume test. 

A pop-up stopper and lever may be included in your waste-and-overflow assembly. If that’s the case, double-check that things are working properly.

These are the steps you need to follow to install the overflow drain. Make sure to follow the steps as precisely as you can!


Question: Why does my bathtub overflow drain have a leak?

Answer: A gasket is installed behind a tub overflow drain. Over time, it will become brittle and squeezed. The gasket would get old after some time and can get fractured. The water from the overflow drain could then leak into the surrounding region.

You quickly need to take help from an expert to fix the issue. Getting late can cause you more issues.

Question: Where does the tub overflow drain take the water into?

Answer: Water that enters the tub overflow hole flows down a pipe immediately. The tub floor drain is connected to the same pipe. In other words, the water from the tub overflow follows the same path. And the water that ordinarily drains from your tub follows the same path.

Question: How can I replace the overflow gasket of my bathtub?

Answer: Remove any existing caulking with a utility knife or scraping tool first. Then, using a screwdriver, remove the overflow cover plate. Then look for the original overflow gasket. Then, by centering the replacement overflow gasket in the overflow aperture, install it. And finally, you’ve completed the gasket replacement.

The Final Words

Now you know how to install a bathtub overflow drain

We hope you find our instructions simple for the implementation. In case you face any difficulty, call a professional for help. 

Best wishes!