Log in
Glossary

Cleanout

Cleanout

A cleanout is a capped pipe that gives a plumber easy access to your main sewer line. You can usually find it in your yard, basement, or near the foundation. Opening this cap lets you clear out clogs without digging up the pipes.

Origin

This is a straightforward combination of the words clean and out from early 20th century plumbing trades. It literally describes the action performed at this access point.

How you'll see it used

  • The plumber quoted us 150 dollars to snake the main line but noted they could not start until we found the cleanout buried under the mulch.
  • Our home inspection report recommended installing an exterior cleanout because the only access to the sewer line was a vent pipe on the roof.
  • I accidentally shattered the PVC cleanout cap with my weed trimmer and had to buy a threaded replacement at the hardware store.

What is a cleanout?

A cleanout is a capped pipe that gives a plumber direct access to your main sewer line. Every time you flush a toilet or drain a sink, the wastewater travels through your home pipes and into a single large pipe underground. This main line carries the waste out to the city sewer or your septic tank. If that main line clogs, water backs up into your house. The cleanout is the entry point to fix that problem. The name comes directly from early plumbing trades. It is literally the spot where you clean out the pipe.

You can usually spot a cleanout by looking for a pipe sticking a few inches out of the ground with a square knob on top. The cap might be white plastic, black plastic, or heavy cast iron. The square knob allows a wrench to grip and turn the cap. Some older homes might not have one outside. In that case, plumbers have to pull a toilet off the floor or climb on the roof to clear a clog.

Where to find your cleanout

You want to know where this pipe is before you have a plumbing emergency. You can usually find it in one of three places.

  • In the front yard: Look between your house and the street. It might be hiding in a flower bed or sitting flush with the lawn.
  • Near the foundation: Walk around the outside of your house. Look for a pipe sticking out of the exterior wall or the ground right next to the wall.
  • In the basement or crawlspace: Older homes often have a cast iron cleanout at the base of the main drain stack indoors.

If you just bought the house, finding this cap is a great task for Your First Week as a Homeowner. Keep the area around it clear. Do not plant bushes right over it or cover it with a patio.

Why it matters for your wallet

Tree roots, grease, and flushed wipes can block your sewer line. When that happens, a plumber needs to run a motorized snake or a camera down the pipe to break up the blockage. If you have an accessible outside cleanout, the job is fast and keeps the mess outside. A standard sewer snaking costs 150 to 400 dollars. Prices will vary based on your location and the severity of the clog.

If you do not have a cleanout, the plumber has to work inside your house. They might charge an extra 100 to 200 dollars just to remove and reinstall a toilet to reach the drain. If your home has no cleanout at all, a plumber might suggest adding one. Installing a new exterior cleanout involves digging up your yard. This project usually costs 800 to 3000 dollars. These ranges vary widely depending on how deep your sewer line is buried.

Do not open it yourself during a backup. If toilets are overflowing inside, the pipe is full of pressurized wastewater. Unscrewing the cap can cause hundreds of gallons of raw sewage to shoot up into your yard or face. Always let a pro handle a backed up main line.

What to watch for

You should inspect the cap a few times a year. Make sure it is screwed on tight. A loose or missing cap lets dirt, rocks, and small animals fall into your sewer line. This will cause a massive clog. It also lets nasty sewer gases escape into your yard. If you notice bad odors near your foundation, a loose cap is often the culprit.

Lawnmowers and weed trimmers often damage plastic cleanout caps. If your cap gets cracked, you can buy a replacement at any hardware store for about five dollars. Just measure the width of the pipe before you go. Taking care of this small piece of Plumbing saves you from massive headaches down the road.

Frequently asked

Can I snake my own cleanout?

You can rent a sewer snake from a hardware store, but it is heavy and dangerous to operate without experience. The spinning cable can break your pipes or seriously injure your hands. It is usually better to hire a professional for main line clogs.

Why does my house have two cleanout pipes next to each other?

A double cleanout setup points in two different directions. One pipe lets the plumber snake toward your house to clear under the foundation. The other lets them snake toward the street to clear the line leading to the city sewer.

Does my city own the cleanout or do I?

You own the cleanout and the entire sewer line running from your house to the street. The city only takes responsibility once your pipe connects to the main city sewer under the road.

More glossary terms

Bypass Diode

Bypass Diode

A bypass diode is a tiny electronic part built into solar panels. It acts like a detour sign for electricity when part of the panel is covered by shade or leaves.

 Scupper

Scupper

This is a drainage hole built directly into the raised edge of a flat roof. It allows heavy rainwater to pour off the roof and into a downspout or away from the building.

 Declarations Page

Declarations Page

This is the first page of your home insurance policy that summarizes your exact coverage. It tells you how much you pay each year, the cost of your deductible, and the maximum payout for a disaster.

 321 Browse all terms Open the glossary →