Main line vs Drain Line – What’s the Difference?

August 22, 2023

You may have heard of our famous Hamilton $99 Mainline special, but did you know it’s actually for a specific line in the home? That’s right, it’s for your home's sewer line.

Residential sewer lines tend to back up when damage or roots are present. These backups are different from a backed up stool, sink, or drain. When your fixtures are backed up, it’s typically an issue with your main drain (or main stack).

If you want to better understand the differences between the mainline and drain line, keep reading.

What is a main line?

Simply put, your mainline is your sewer line. It’s the line that goes from your house to the city connection or your septic tank. Before leaving your home, all of your drains dump into your mainline. When your mainline backs up, it is important to know where your cleanout is located.

All homes should have a clean-out for the mainline. It’s usually inside your home in the lowest portion of the home or outside of your house. If you don’t have a cleanout, a plumber will most likely pull a toilet and run the line through there; although the extra work will add more cost.

When you are having an issue with your mainline, you may also be experiencing other plumbing issues in your home. When you see a back up in the lowest part of your home that usually includes sewage, then you can safely guess that you are having an issue with your mainline.

What is a drain line?

You have many drain lines in your home. Examples would include, sink drains, shower drains, and toilet lines. When these are having issues, you most likely will be able to use the plumbing everywhere else in the home because they are not connected. Sometimes, if one drain is having trouble, the other drains in the room, if connected, may act troublesome as well. Bathrooms tend to have multiple drain issues stemming from one major problem.

Why should I know the difference?

Knowing the difference between the mainline and the drain line is important because they are two different things and are priced differently. The fixes for these lines are different as well. The mainline can be inspected with a camera to identify the problem at hand but a drain line cannot. Sometimes, a severely damaged mainline will require a crew to dig up all or part of your yard to get to the sewer line.

A regular drain line would be fixed by a plumber who will be working inside the home the entire time. Often, these pipes are too narrow to send a camera all the way through.

Symptoms of a main line clog

There are a few things to look for to figure out if you’re having an issue with your mainline or a drain line. The first thing to look for is where the back-up is located. If it is in the lowest part of your home, there is a chance it could be the mainline. If there is sewage coming out, it most likely is. If you hear gurgling in a different area of the home when using any water, there could be a mainline issue as well.

If you are seeing any of those symptoms for your mainline, call us to take advantage of our $99 mainline opening special. It comes with a free camera inspection. If you are having issues with any other drains, still give us a call at (913) 227-4943 because we can still help with those issues too.

Last Updated: August 22, 2023