How To Seal Off Bathtub Overflow: Step-By-Step Guide 

Soaking in a bubble bath after an eventful day is one of the best things in life. But if you have a standard tub, you might feel that it never fills enough. The pesky overflow drain prevents the water from going all the way to the top. If you are a taller person, that means your shoulders or toes will always be out of the water – thus, a part of your body will never get warm. Now you might wonder, is there a way to seal off the bathtub overflow? Luckily, there is. Here’s how to do it.

How To Seal Off Bathtub Overflow

An overflow drain is an essential part of the bathtub. Its role is to collect the water and prevent it from leaking all over your bathroom floors if you accidentally leave it on. Technically, you should never cover this drain with a stopper. That said, you can seal it off with an overflow plate, a closing cover, or a removable cover.

Things You Will Need

  • Bathtub overflow plate or cover
  • Overflow gasket
  • Screwdriver
  • Caulk
  • Putty knife
  • Straight edge razor
  • Pliers

1. Select And Buy A Bathtub Overflow Cover Or Plate

Overflow drains have a functional role, and the Uniform Plumbing Code specifically requires all bathtubs to have such a drain. This means that you can’t seal off a bathtub overflow if you want your fixture to comply with the code.

That said, there are options to work your way around the code. The most common solutions include a closing bath overflow cover or a rubber cover with suction cups that you can apply to the drain and remove as needed.

Alternatively, you can remove the standard cover and replace it with a permanent overflow plate. We wouldn’t recommend this solution, as it would make it hard to use the tub’s overflow drain if necessary. However, the option is there.

From all options above, a rubber (or silicone) cover is the cheapest. Acting as a bath overflow hole stopper, this cover type goes over the existing bath overflow drain cover and attaches to the tub wall with suction cups. If you need to use the overflow drain, simply pull it off – this cover doesn’t require a semi-permanent or permanent installation.

A closing cover replaces the standard strainer-type hole cover that comes with your tub. This cover type is more similar to a bottom drain stopper. You must fix it in place of the standard cover, and can turn it one way to close it (and allow the tub to fill to the brim) and the other way to open it (allowing the water to drain).

An overflow plate also replaces the standard hole cover, but it has no openings. It is permanently installed on your tub, and it is a good choice if you’re sure you’ll never have to use the overflow drain.

2. Remove Your Tub’s Standard Overflow Cover

Most manufacturers cover the bath overflow drain holes with plates that have one or more openings, but that increases the tub’s aesthetic appeal. To install a closing overflow cover or plate, you must remove the original cover first.

Generally, manufacturers fix this cover with two lateral screws. In rare cases, they glue it in place with a caulk or plumber’s putty.

Check your tub and see how the cover is installed. If it is fastened with screws, use a flathead or cross-head screwdriver to remove them.

If the cover is sealed with caulk, use a putty knife to remove as much of the caulk as possible from around the cover, then pull it out of the drain. You should generally be able to grab and pull it with your hands but if you can’t, use a pair of pliers to remove it. Once you’ve removed the cover, pull out the gasket sealing the overflow.

3. Clean The Drain Hole

Once you have removed the original cover, inspect the drain hole for any traces of gasket or caulk. If the opening isn’t clean, use a straight-edge razor to remove any rubber or caulk pieces. You can then clean the area with an all-purpose cleaner before proceeding.

4. Install The Closing Overflow Cover Or Plate

Line up the new gasket with the overflow opening, making sure the thicker side faces down. Gently push it in place.

Before buying the gasket, check the new cover or plate you want to install – most of them have a gasket in the pack. If yours doesn’t have one, buy a suitably sized gasket from your home improvement store. Never reuse the original gasket you took off.

Once the gasket is in place, align the new cover or plate with the hole, positioning the screw holes in correspondence to the notches on the tub. Fasten the cover with the provided fasteners. Seal with silicone caulk around the cover when you’re done.

5. Test The New Cover Or Plate

All you have to do is close the new overflow cover if you opted for a closing one and fill the tub to the brim. If you used a plate, simply fill the tub.

Wait for about 15 to 30 minutes and check the water level in the tub. If the closing cover works properly, you should find the tub filled to the brim when walking in the bathroom. However, if the water level has dropped, you may want to remove the cover and reinstall it, as it may lack proper sealing.

Frequent Questions

How to block overflow drain in tub DIY?

Don’t want to replace the original overflow cover and didn’t find a rubber stopper at your home improvement store? There are a few DIY overflow drain cover alternatives you could use if you don’t feel like going to the shops. These include sealing the overflow drain with waterproof tape before filling the tub, filling the drain cover’s holes with flex sealant or waterproof sealant, or plugging the overflow drain hole with a rubber plug or washcloth placed in a plastic bag to prevent it from soaking.

Can you plug an overflow drain?

You can plug an overflow drain with a rubber plug or a washcloth. To do this, you have to remove the standard drain hole cover first. Use a rubber plug that is slightly larger than the overflow drain hole to ensure a perfect seal. If you decide to use a washcloth, place it in a plastic bag and then stuff it in the hole. The bag will prevent water from soaking into the cloth and eventually leaking into the drain.

Can you remove the bathtub overflow drain?

No, you cannot remove the bathtub overflow drain. Bathtub overflow drains are required by the plumbing code and are essential to minimize the damage if you accidentally forget the faucet on. Are you concerned about a bathtub overflow leaking through the ceiling? As long as your plumbing system works properly, such leaks are improbable to happen.


Sealing off the bathtub overflow is easy, but you should consider solutions that allow you to use this drain when needed. You should also only keep the overflow drain plugged when you want to soak in the tub. Forgetting to unplug it when you’re done means that other family members or roommates could accidentally flood the bathroom. We hope this guide can help you pick the right option. If you’re in doubt, don’t hesitate to contact a licensed plumber.

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