skip to Main Content

Sanitary Sewer Cleanouts: What Are The Requirements?

We are always seeing updated plumbing on many older homes. The old cast iron and galvanized DWV pipes are being replaced with PVC. Because of the ease of installation, many times these upgrades were performed by homeowners or amateurs. I rarely see enough cleanouts or cleanouts located at the proper areas. According the 2015 ICC Plumbing Code Section 708; cleanouts should be located in intervals not to exceed 100 feet. The junction of the building drain and the building sewer shall also have a cleanout. Where a horizontal drainage pipe, a building drain or a building sewer has a change of horizontal direction greater than 45 degrees, a cleanout shall be installed at the change of direction. These three standards are most understood, and often installed. Here are other requirements a home inspector should be looking for:

  • Cleanouts shall be the same size as the piping served by the cleanout, except that cleanouts for piping larger than 4 inches need to be larger than 4 inches
  • Cleanouts for 6-inch and smaller piping shall be provided with a clearance of not less than 18 inches. Cleanouts for 8-inch and larger piping shall have a clearance of not less than 36 inches
  • Cleanouts shall not be installed in concealed locations including inside plenums, within walls, within floor / ceiling assemblies, below grade and in crawl spaces where the height from the crawl space floor to the nearest obstruction along the path from the crawl space opening to the cleanout location is less then 24 inches.
  • Cleanouts with openings at a finished wall shall have the face of the opening located within 1 ½ inches of the finished wall surface
  • Cleanouts located below grade shall be extended to the grade level so that the top of the cleanout plug  is at or above grade
  • The use of a threaded cleanout opening to add a fixture or to extend piping shall be prohibited except where another cleanout of equal size is installed with the required access and clearance
  • A removable P-trap with slip or ground joint connections can serve as a cleanout for drain piping that is one size larger that the p-trap size
  • A toilet is not considered a cleanout
  • Cleanouts located on stacks can be one size smaller than the stack size
  • Cleanout plugs shall have a raised square head, a countersunk square head or a countersunk slot head
  • The installation arrangement of a cleanout shall enable cleaning of drainage piping only in the direction of drainage flow
  • Test tees can serve as cleanouts

Related Articles:


Want To Learn More? Click HERE to Search Our Full Database Of Home Inspector Newsletters.


Brought to you by InspectCheck

Try InspectCheck for free at

Back To Top