There are many fail-safes in modern plumbing to help prevent sewer issues. From drain traps to sump pumps and vent pipes, your home is well-protected against sewage backups. One very important component to this system which you should be aware of is the sewer clean out.

Despite its innocuous appearance, having one or more clean outs may have a major effect on both your home’s sewer line health and on your bank account.

What Is a Sewer Clean Out?

The sewer clean out is a capped pipe located on or near your property line which connects to the lateral sewer line. A lateral sewer line is the pipe that connects your home’s sewer lines to the municipal sewers or your septic tank.

When the lateral clogs, it can cause sewage to back up into the drains, creating both a mess and health hazard. Having a sewer clean out enables you to keep the lines clear and drain water if a backup occurs.

How to Find the Sewer Clean Out

The sewer clean out is a small capped pipe jutting above the ground. Unfortunately, locating it is not always simple. To make matters more complicated, many homes have multiple clean outs and, in some rare cases, may actually have the clean out located inside. The following steps should help you find the clean out more easily.

In many municipalities, the place where your lateral meets the municipal sewer line is marked. Check for a stamped or painted letter ‘S’ along the curb and sidewalk. If you find this marking, you can easily imagine a straight line from the mark to your home under which the lateral may be found. In some cases, you may even be lucky enough to find a clean out in the vicinity of your search.

In many cases, placing the sewer clean out near the road proves inconvenient, or the home’s previous owners chose to have more than one sewer clean out installed. Sewer clean outs are also generally located near the home when you have a septic system in place. The cap is rarely found beyond three feet from the foundation and will be between the road or septic tank and the place where your home’s sewer line passes through the foundation into the ground.

Some homes, especially older ones, may have clean outs located inside or protruding from the outer walls. Check basements, crawl spaces, and the attic along the vent pipe for possible locations. In many cases, indoor sewer clean outs will appear to be a ‘Y’ or ‘T’ shaped intersection where one side is capped. Although not required, these are useful for maintaining your indoor pipelines.

What if the Property Lacks a Sewer Clean Out?

Older homes may not have a sewer clean out. This is especially true if one is not required by local or state plumbing codes. In such cases, it is generally best to have one installed.

There are also some instances where your home has a clean out which has simply become covered by dirt. If you believe the home has one but were unable to locate the cap, you may choose to do some light digging along the ground where you believe the clean out should be.

Alternatively, you may pay a plumber to run a camera through the line to locate the clean out from inside the pipe and pinpoint where to dig.

Benefits of a Sewer Clean Out

While having a sewer clean out is required by law in some states, you might be lacking one if you have an older home or are in a state where they are optional. However, there are several benefits to having a clean out installed on your property:

Lower Maintenance Costs

The clean out allows direct access to your property’s sewer lateral. This means a plumbing expert can monitor the water flow from each tap in your home individually to ensure there are no blockages or other pipe issues during their regular maintenance visits.

Cheaper and Easier Cleaning

Normally, a plumber would have to remove your toilet or even go onto the roof in order to clean your sewer lines. By having a sewer clean out, they will have easy access to the sewer lateral. The savings in time and effort equate to a smaller bill for you.

Protects Your Landscaping

One benefit which becomes apparent only in an emergency is the fact that the sewer clean out can help prevent the need to dig up your yard in the event of a major clog.

Unlike many of the pipes inside your home, the sewer lateral is located completely underground and therefore cannot be examined for wear or damage without excavating it. The sewer clean out provides an access point through which your lateral may be more easily inspected.

Backflow Prevention

In the event of a major clog, the clean out acts as an external drain. Uncapping the clean out will allow you to drain the excess water, preventing it from flooding your home. This may also prove useful if there is an issue with the municipal sewer that is forcing water back up into your lateral.

How to Install a Sewer Clean Out

Installation of a clean out is a multi-step process. In some cases, your local municipality may provide programs to help with the cost of installation, especially in cases where having a sewer clean out was not previously required by code. Be sure to check for any such programs or grants, as well as any required permits before starting.

Also, if you do not have experience splicing or installing sections of pipe, it may be best to hire a professional to avoid costly mistakes.

1. Choosing a Clean Out Type

The first major step before beginning work is to pick the type of sewer clean out you wish to use. There are currently three options available:

The most popular type used for modern installation, the double clean out has two shafts that connect to the lateral pipe forming a ‘U’ shape. The cap closer to your home provides easy access to the city end while the cap closer to the street allows you to maintain the house end of the lateral.

This type provides easy access to the municipal end of your lateral, although the 45 degree angle does not allow for access to the full pipe.

This T-shaped clean out permits access to both ends of the lateral but can be difficult to use for clearing blockages due to the 90-degree angle at the intersection.

2. Excavation and Installation

You will need to locate your lateral and excavate a section of pipe. This may be done with either common tools or rental equipment, being careful not to damage the lateral pipe. Once you have the desired portion of pipe fully exposed, you should measure out the section you will be cutting away. The cutting tools you need will vary based upon the material your lateral pipe is made of.

Once you have removed the unwanted section, you are free to measure, cut, and install the new junction. Knowledge of plumbing is essential here, as you will need to fit and install the replacement section, verify the plumb, and make sure it is waterproof before filling the hole and capping the new clean out.

It is usually best to fit a container box around the cap so that it doesn’t become overgrown or buried easily.

Professional Cleaning Cost with a Sewer Clean Out

Even though cleaning your own lateral line may seem like a cheap alternative, there is always a risk of damaging the pipes. Having a professional plumber do the work is more effective and will be cheaper if they have access through a sewer clean out.

This is because they have more direct access, requiring fewer tools and less labor than if they have to dig up your yard or snake the lateral from a point inside the home.

HomeAdvisor gives a basic estimate range of $99 to $900 with an overall average of $288. This does not include additional fees for using a camera or water jetter.

CostHelper provides more detailed cost breakdowns, estimating the cost of snaking your lateral between $148 and $900 with an average cost of $410. They note that the distance snaked plays a role in your overall cost, making it less expensive to snake the lateral from an external clean out than from an access point inside the home.

In addition, a camera inspection of the line will run between $100 and $800.

Today’s Homeowner Tips

When choosing to have a professional come in, make sure they are certified and have a good reputation. Some plumbing companies will offer a flat rate but pressure you to get additional services to inflate the price. Make sure to shop around carefully for the best balance of quality and cost.

Use the form below to get price estimates from local plumbing providers:

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Henry Parker

Henry Parker is a home improvement enthusiast who loves to share his passion and expertise with others. He writes on a variety of topics, such as painting, flooring, windows, and lawn care, to help homeowners make informed decisions and achieve their desired results. Henry strives to write high quality guides and reviews that are easy to understand and practical to follow. Whether you are looking for the best electric riding lawn mower, the easiest way to remove paint from flooring, or the signs of a bad tile job, Henry has you covered with his insightful and honest articles. Henry lives in Florida with his wife and two kids, and enjoys spending his free time on DIY projects around the house. You can find some of his work on Today’s Homeowner, where he is a regular contributor.

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