Bathroom Sink Drain Plumbing!

Bathroom sink drain:

A bathroom sink drain is also known as the wash bowl or lavatory sink drain.

What is so important about this particular drain that you need to know about? Well, just like the kitchen line, you will also need to learn about the lavatory piping in general because it will save hundreds of dollars if you understand the system.

The wash bowl system is one of the shortest lines in your home and it could be one of the easiest ones to maintain it.

However, it will not always be easy to clean such a line, in fact, there were times that I unplugged it in minutes while other times, I literally spent hours working in the drain unsuccessfully.

As you are going to find out in the next paragraphs, the main reasons are the followings: the size of the pipe, the system design and finally, the number of turn existent in the line between your access point and the main drain.

The main components of a sink drain:

A wash bowl drain consists of the pop up assembly including the tale piece and p-trap that can be located under the sink and the actual piping the goes from behind the sink in the wall all the way to the bigger piper (main drain).

How to know the length of the line?



To answer this question you must first to understand how your home plumbing was done. But if you don’t that, don’t worry. I will give a very important clue: all drains in your home are connected to the bigger pipe, also called main drain or main sewer line.

Learning how to locate the sewer line in your home, will help you estimate the length of all the other drain lines because they all must be connected in the main drain.


Back to the bathroom sink drain piping. As you might have noticed, a bathroom sink is mostly located on the left or right side of the toilet.

The toilet is the only drain that is directly connected to the main sewer line; therefore, by knowing this, you will also be able to determine how long your lavatory drain piping might be.

This secondary drain usually goes through the wall and connected directly in the main sewer pipe, which in most cases is only 2 to 5 feet in length.


The pipe size of a lavatory drain:

What is the common pipe size for a lavatory drain? It depends on the age of the house.

If your house was built more than 30 years ago, it is likely that your bathroom sink piping will be galvanize material and it will have measurement of either 1 ½” or 1 ¼’’ in diameter.

However, according to the plumbing code, the 1 ¼” pipe is no longer a legal size to install in drain lines.

If your house was built less than 30 years ago, it is likely that your home plumbing system is made of white PVC or ABS piping (black plastic). In the newer homes, you will find out that the common pipe size for secondary drains will measure either 1 ½” or 2” in diameter, which is the newer plumbing code.

Unclog a bathroom sink drain:

How to unclog a bathroom sink drain?

In the page unclogging your drain you will find a link that will take to the page of how to unclog your bathroom sink drain.

I hope that you will find this information to be useful to you and that will help to enlighten you knowledge. As always, if you have comments or suggestions, just send us an email. Thank you!

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