What Size Pipe For Main Sewer Line You Should Use! Don’t Connect Wrong

A common question is what size pipe for the main sewer line? The answer depends on what type of main sewer line you are installing. Generally, a 3 to 6 inch can do the job, but you must know the sewer line before you connect.

The main sewer line is the pipe that drains water and waste from your home to the city sewer system. It also carries stormwater runoff and sewage from other homes to the treatment plant.

This line transport wastewater from your house to public sewer system. However, The size of the pipe you need will depend on how big your house is or how far away the public sewer is. 

If you’re looking for the size to install a new sewer line, you can read out this article. Meanwhile, we try to provide all necessary information about pipe size for the main sewer line.

What Size Pipe For Main Sewer Line

4-inch main drainage pipes are common for connecting to the sewage pipe or municipal sewer. At present, all sewage drainage lines for toilets have diameters ranging from 3 or 4” sewer line. The greater the width of the pipe, the more rubbish it can transfer.

But the question is,what size pipe for toilet drain can we use? A 4-inch pipe can transport approximately twice the amount of garbage as a 3-inch pipe.

READ ALSO  Know All the Pros And Cons Of Well Water

A Brief Guide on Main Sewer Line Pipe Size

If it’s about a new house, you have the option of installing arounf 4 inches toilet drain pipe sizefrom each toilet. However, you can also choose to have a 3 inchpipre line from the house to the main sewer line.

If you’re dealing with a 3-inch drain in an older home, you’ll have to work or renovate it. However, If you have many toilets on a 3-inch line, be aware that clogs are more common. The toilet drain pipe size is 3 inch in diameter, but if any issues arise, you can consider 4 inch.

In your bathroom, a perforated pipe delivers wastewater to the apartment’s central drainage system. The standard toilet drain pipe size in most residences is 4 inches in diameter. Drainage from a house is typically handled by 3-inch pipes that convey water to the toilet. However a 4-inch pipe you can utilize for this purpose.

What size drain for toilet should I use? You may be wondering right now. A toilet requires a 3-inch drain pipe generally unless your 2 toilets share the same drain. If they do not share the same drainage, then you can manage a 4-inch waste pipe.

Still Confused?

Listen, if you cannot determine toilet waste pipe size, you can measure from the wall behind your toilet to the floor. In most cases, the diameter of a toilet waste pipe is 100 millimeter. However, with all the interior surfaces up, locating a pipeline in a freshly allocated basement bathroom can be challenging.

Now we can think you may find your questions answered to “what size drain pipe for toilet?” Toilet sewer pipe sizes range from 3 inches to 6 inches, depending on how many washrooms you have in your home.

The drainpipe attaches to the bathroom basin, which is 3 inches. There is no method of reducing the tube’s diameter at any point in the plumbing. It is necessary to have a 4 inch drain pipe installed if you have three or more bathrooms in your residence.

READ ALSO  What Plumbing Work Can Be Done Without A License?

When connecting to the toilet drainage system, you must ensure that the bathtub drain does not hook to the pit arms. A pit arm will require to link your main drain connection that is your bathroom’s main drain. If in which case there is no other way for the shower you connect.

A Helpful Tutorial You May Need!

Frequently Asked Questions (FAQs)

Should I use a 3 inch or 4-inch sewer pipe?

It depends on your toilet drain size. If your house is new, then you can install a 4-inch sewer pipe. And if your house is old, then you can install a 3-inch sewer pipe. On the other hand, if you want to share one drainage pipe for two bathrooms, you can install a 3 inch pipe. But we recommend each drainage for one 4 inch pipe.

Is 3 sewer pipes big enough?

In most cases, a 3 inch pipe is sufficient. On the other hand, if your home has 3 or 4 drains for toilet, you can utilize a three-inch sewer line easily.

Can you use a 3 inch pipe for the sewer line?

Yes, you can use a 3-inch pipe for the sewer line if your house is old. On the contrary, according to your construction regulations, toilets must have a 3-inch discharge. So, if you think you have 3 or 4 sewer lines, you are wondering what size you will use. You can buy a three inch diameter pipe.


You no longer have to consider what size pipe for the main sewer line. Regardless of the material used here, a sewer drain is unquestionably an object you want to function well. It is not always wise to have a larger sewer drain.

Proper pipe size assures that sewer effluent flows away as fast as possible from the residence. Be sure to consult with competent employees and conduct a thorough study on the size you want to employ before you begin spending the money.

You Can Also Read:

Check out our Reusable Bamboora Paper Cloth Towels

While shaping the aim of making the environment clean and healthy, Bamboora deals with the production of natures way bamboo paper cloth towels. These bamboo towels are better for the environment.
Along with doing lots of plumbing work, they are usable for other house chores too. From wiping out the spill on the floor to cleaning the dust, bamboo paper towels effectively perform their work. They are effective in replacing regular cloth towels that you often purchase. The natural strength and softest fiber of bamboo make them one of the best sustainable bamboo paper towels.

Similar Posts