Are Toilet Flappers Universal? (Explained)

Canister/Tower-flush Valve System.

There’s nothing worse than an unexpected trip to the hardware store for a replacement toilet flapper during an already-busy week, except having to return to the store because you bought the wrong one the first time around. Before buying any new parts for your toilet, including a toilet flapper, you should make sure that you are buying the right one.

When they have to get a replacement, many people wonder, are toilet flush valves universal?

When a flapper’s packaging says it’s universal, that just means it works with toilet systems from many different brands. You still have to check that you’re getting the right size, because neither flappers nor toilet flush valves are completely universal.

It can be confusing to pick up a flapper that was labeled as a universal part and realize that it doesn’t actually fit your toilet when you get home, but hopefully after reading this blog, you’ll understand the distinction.

Are Toilet Flush Valves Universal?

The toilet flush valve is the part of the toilet that the flapper attaches to. The flapper is a small piece of rubber or plastic that blocks water from flowing from the tank to the bowl through the flush valve until you activate the flushing mechanism.

Knowing if your flush valve is universal is important if you have to replace your toilet flapper because you have to get the right flapper for the mechanism.

Toilet flush valves are not perfectly universal. Although the mechanism works the same on all toilets, it varies slightly in terms of size and shape. These small variations matter when looking for a replacement toilet flapper.

Older toilets had standardized flush valves that were all the same size, 2 inches wide, and shape. However, newer toilets have a lot more variation.

Now, toilets with flush valves that are 3-4 inches wide are more common because these toilets use less water. The wider valve allows more water to rush in at a time when you flush, which generates a more powerful flow that paradoxically uses less water over time. Modern flush valves also come in a few different shapes depending on the mechanism.

For example, some toilets have tower-style flush valves that create a 360-degree flow when you flush. These types of valves use flush valve seals instead of flappers (Link), so replacing them is a whole different ball game.

Another common type of flush valve is the dual-flush valve, which adjusts water flow depending on the button you press.

Recent changes in the size of flush valves means that replacing your toilet flapper comes with the extra step of determining that you’re getting the right one, but manufacturers didn’t make this change just to make your life more difficult.

The overall savings on your water bill are worth the slight hassle when you have to replace your flapper and are just checking to make sure you’re getting the right one.

Why Does Getting The Right Size Matter?

Toilet flappers may vary a little based on size, but they all work in the same way. In that case, why does it matter if you get a 3-inch flapper for a 2-inch valve if the flapper still does its job?

The problem is that a toilet flapper only does its job, which is to prevent water from leaking into the bowl when you’re not actively flushing the toilet, if it fits to the flush valve perfectly. A flapper that is too large or too small will not fit to the valve properly, allowing water to leak through.

How To Ensure You’re Getting The Right Size Toilet Flapper?

Now that you know that the size of the flapper is important, how do you make sure that you’re getting the right one? The easiest way is to check the manufacturer instructions.

When you get a new toilet, you also get a pamphlet with everything you need to know about your new porcelain throne. This pamphlet also includes specifications about the different parts, including the toilet flapper, and which ones to get when you are looking for a replacement.

Certain manufacturers only accept flappers that fit their brands specifically, so it’s always good to double-check.

Some will even send you a replacement for free so that you don’t spend money on generic flappers that won’t work. If you lost your instructions (and don’t worry, it happens to the best of us), all is not lost.

Measuring your toilet flapper is easy. Just turn off the water supply to the tank, remove the flapper, and measure the opening to the flush valve.

If the diameter is 2 inches, then get a 2-inch flapper, and if it measures 3 inches, get a 3-inch flapper.

If you don’t have a tape measure, you can always estimate the diameter by comparing it to a common household object such as a baseball or taking the flapper with you to the hardware store and asking someone to help you.

Whatever you do, don’t just grab any flapper thinking it will fit, because that will just cause frustration down the line if you grabbed the wrong one.

What Does It Mean If A Package Says A Toilet Flapper Is Universal?

So, you’ve just learned that flappers (and toilet flush valves) are not universal and actually vary quite a bit in size, but when you go to the hardware store, you notice a range of flappers claiming to be universal. What is that all about?

Before you report manufacturers of “universal” flappers to the Better Business Bureau for false advertising, you should know what it means when toilet flappers claim to be universal.

That just means that the flapper works with most brands of toilets instead of fitting to a specific brand. Even universal flappers vary in size, and you’ll see that the label will say if the flapper fits a 2-inch or 3-inch flush valve. The advantage of universal flappers is that they are usually more affordable than buying a brand-specific flapper.

However, some toilets require toilet flappers from that specific manufacturer. The best way to tell if that’s the case for your toilet is to check the manufacturer instructions or look around online for other user experiences before buying a universal flapper.

What Are The Most Common Types Of Flappers?

Besides differing in size, toilet flappers sometimes differ in terms of shape and fit. Here are some of the most common types you should keep in mind.

Flexible Vs. Solid Toilet Flappers (Which One Do I Choose?)

Flexible flappers have a bit of stretch and are usually made of rubber, while solid flappers are made of rigid plastic that doesn’t bend. You should try to get the same type of flapper that was already on your toilet. If you’re not sure which one you have, try touching the edges of your flapper and see if they give at your touch, or if they’re rigid.

Do I Choose A Non-Adjustable Or Adjustable Toilet Flapper?

Most toilet flappers you find in the hardware store today are adjustable because most modern toilets work with this type of flapper. However, toilets manufactured before 1994 have to have a non-adjustable flapper.

What Shape Toilet Flapper Will Fit My Toilet?

Most toilet flappers today are rubber or plastic covers with two ears that attach to the toilet.

Other common shapes include the seat disk, which is a flat plastic disk most common in older toilets, and the tank ball flapper, which is shaped like a ball.

While most toilet flappers you find nowadays are the modern rubber kind, and those flappers will fit most flush valves, if your toilet has one of the rarer toilet flapper types, you should track down a replacement that is as similar to the original as possible.

Frequently Asked Questions

Here are some of the other questions people usually want to know when replacing their toilet flapper.

How Do You Replace A Toilet Flapper?

Once you get the right toilet flapper, replacing it is very easy.

Just turn off the water supply to the tank, lift the old one out of its chain, and put the new one in. Be sure to adjust the chain to the proper length.

If you’re unsure about how to replace the flapper, or the instructions on the package are unclear, you can always refer to YouTube videos such as this one. (Link)

What Is An Old-Style Toilet Flapper?

When people talk about an old-style toilet flapper, they’re usually referring to the standardized 2-inch toilet flapper disk. Older toilets had less variation in terms of flush valve and toilet flapper, so in many ways replacing the flapper on an old toilet is easier because you almost always know which size you need.

However, newer toilets justify their complexity thanks to their ability to save water.

Why Does Choosing The Right Toilet Flapper Matter?

When you see a universal toilet flapper in the hardware store, that just means that the flapper can fit flush valves on most brands of toilets, not that it will automatically fit yours.

Flappers differ primarily depending on their size, although some toilets require strangely shaped flappers.

Picking the right size flapper is crucial because you need to have a good seal between the flapper and the flush valve. Taking the time to measure the valve can save you headaches down the road.