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What Size is Bathroom Sink Drain Pipe? (Answered)

The bathroom sink drain pipe can leak or get damaged due to various factors. Replacing the sink drain pipe can be quite a hassle if you don’t know its size.

So, you might be eager to know what size the bathroom sink drain pipe is and how to measure it. Let’s find the answers to all your queries.

What size is the bathroom sink drain pipe?

The size of the bathroom sink drain pipe mainly depends on the size of the drain holes’ outlet. If the size of the outlet is 1.5-inch, the size of the sink drain pipe should be 1.5-inch. Nowadays, sink drain pipes of all sizes are available. You will just have to measure the pipe accurately.

What is the standard drain pipe size for bathroom sinks?

The drain pipe size for bathroom sinks can vary from sink to sink. However, a standard-sized drain hole is installed in most bathroom sinks these days, providing a general size for all drain pipes.

Sink drain pipes of 1.25 inches are the standard drain pipe size for bathroom sinks, according to the international code council. Drain pipes for bathroom sinks of sizes 1.5 and 1.625 inches are also commonly used.

How big are bathroom sink pipes?

The bathroom sink pipes are not that big, as the bathroom sink has a lower chance of getting clogged. They mainly connect the drain hole to the tailpipe to pass the water in the sink basin to the drainage system.

The bathroom sinks are usually used for hand and face cleaning with soap, handwash, face wash, shaving cream, and more. These elements are in liquid form, so they have no chance of getting stuck in the sink pipe.

As a result, the bathroom sink pipes usually are 1.25 or 1.5 inches wide.

What is the size of PVC pipe used for bathroom sink drains?

When it comes to bathroom sink drains, PVC pipes are perhaps the most common type. The PVC pipe used for bathroom sink drains comes in different sizes so that they can be installed in different drain hole outlets.

The most common size of PVC bathroom sink drain pipes is 1.25 inches. The pipes of this size fit in most bathroom sinks without any issue.

The PVC sink pipes are also available in 1.5-inch sizes. This one is a little larger than the regular size, but it also provides additional connections. The drain pipe of this size has the ability to connect up to three units in a horizontal stack.

Are there any different sizes of bathroom sink pipe? What are the sizes?

As the fitting of the bathroom sink pipes depends on the size of the drainage hole, there are different sizes of sink drain pipes available. Due to the availability of sink drain pipes in various sizes, installing them has become much simpler and more convenient.

The most common and standard size of bathroom sink pipe available is 1.25 inches. This size is basically the diameter of the drain pipe.

Then again, you will also find sink pipes of diameter 1.5 inches. They offer four units connected vertically and three units connected horizontally.

The pipes are also available in 2 inches sizes. This drain pipe can be linked to a horizontal stack of up to six units and a vertical stack of up to ten units. The bathroom sink drain pipes also come in the size of 3-inch and 4-inch.

Let’s take a look at the different sizes of bathroom sink drain pipes available.

SL. No.Sizes
11.25 inches
21.5 inches
32 inches
43 inches
54 inches

How to measure bathroom drain pipe size?

Before getting a new sink drain pipe for your bathroom, you will have to measure it properly to get the perfect sized unit. To get the correct measurement, you will have to follow a few steps.

Here are steps to measure the size of the bathroom drain pipe accurately.

Get the right tools:

By getting the necessary tools to measure the bathroom drain pipe before starting measuring, you will make the whole process simpler. Here are the tools that you will definitely need to measure the sink drain pipe –

  • Large adjustable wrench
  • Plumbing measuring tape
  • Channel-lock pliers
  • Lubricant

Drain the pipe:

The shape of the sink drain pipe is normally U-shaped, so water might remain in it even if the pipe is not used. So, before measuring the rain pipe, you should drain the water and empty the pipe.

Remove the existing sink drain pipe:

You will get more accurate measurements by removing the sink drain pipe before measuring it and the drain hole. You can use the adjustable wrench to detach the drain pipe from the drain hole outlet.

Measure the drain hole:

Measure the drain hole outlet of the sink basin of the bathroom with a tape measure. This is the diameter of the drain pipe. While measuring the size, remember to take notes of the measurements.

Measure the length and width of the pipe:

Now that you have measured the drain hole outlet, you know the size of the installed sink drain pipe. However, by specifically measuring the length and width of the existing pipe, you can get the best unit and prevent any leakage.

Measure the width and length of the sink drain pipe using a measuring tape. In addition to that, measure the diameter of the pipe with a scale to get the exact value.

Can a bathroom sink drain into a 2 inch pipe?

A bathroom sink with a 2-inch or 2.25-inch drain hole outlet can definitely drain into a 2-inch pipe. The 2-inch pipe is quite wide, and the drain pipes of this size are mostly used in bathroom sinks that are heavily used.

The sink won’t drain properly, and water will leak if the pipe doesn’t fit into the drain hole properly. If the 2-inch pipe doesn’t fit properly in your bathroom sink, then don’t worry.

You can use a pipe extender to properly install it to the drain hole outlet and make the bathroom sink drain.

What is the standard bathroom sink drain diameter?

Although the design, color, and size of the bathroom sinks vary from unit to unit, the width of the drain hole outlets is pretty standard. The standard bathroom sink drain diameter is 1.25 inches.

It is declared as the standard size for bathroom sink drain pipes by the international code council.

Are bathroom sink plugs all the same?

The size of most bathroom sink plugs is 1.5 inches. This size is the width of the plug. However, the bathroom sink plugs are also available in various other sizes according to necessity. Thus, all bathroom sink plugs are not the same.

What is the pipe under the bathroom sink called?

The pipe under the bathroom sink is known as P-Trap. It’s a two-part pipe that helps water and other wastes to be disposed of in the drainage system. There is a bend in the pipe, which stops sewer gases from entering your bathroom and your house.

How to replace the drain pipe under the bathroom sink?

To replace the drain pipe under the bathroom sink, first, you will have to detach it from the drain hole with a wrench. After that, you will need to get a new bathroom sink drain pipe of the right size.

Finally, install it using an adjustable wrench, just the same way you detached it.

Final Thoughts:

The usual size of the bathroom sink drain pipes is 1.25 inches. However, it is not mandatory that this standard-sized pipe will fit in all sinks. The size can vary depending on the size of the drain hole. It is essential to get the drainpipe of the right size to prevent any leakage of water.