Sewer Line Cleanout Access Installation Guide

What Is a Sewer Cleanout

A sewer cleanout is a capped access point in your drain or sewer line that allows plumbers to insert cleaning equipment directly into the pipe. Without a cleanout, accessing the sewer line for snaking or camera inspection requires removing a toilet or working through smaller drain openings, which is less effective and more expensive. Most plumbing codes require at least one cleanout at the point where the building drain exits the foundation and another near the property line or municipal connection.

Types of Cleanouts

There are several types of cleanouts. A two-way cleanout has openings in both directions, allowing access upstream toward the house and downstream toward the sewer main. A single-direction cleanout provides access in one direction only. Indoor cleanouts are typically flush-mounted in the basement floor with a brass or plastic cover. Outdoor cleanouts are extended to the ground surface with a riser and cap, sometimes enclosed in a valve box for protection. The most useful location for a cleanout is at the point where the sewer lateral leaves the building foundation.

Installation Process

Adding a cleanout to an existing sewer line requires cutting into the pipe and installing a wye or tee fitting with a removable plug. For indoor installations on PVC pipe, mark the cutting location, cut the pipe with a reciprocating saw, and install a cleanout wye with appropriate couplings. Ensure the cleanout arm extends upward and is accessible — flush with or slightly above the floor level. For outdoor installations, the cleanout should extend to the ground surface with a threaded cap and be clearly marked so it can be found when needed.

Maintaining Your Cleanout

Keep cleanout locations accessible and clearly marked — do not bury them under landscaping, concrete, or storage. Check cleanout caps periodically for cracks or deterioration — a damaged cap can allow debris, groundwater, or pests to enter the sewer line. Replace rubber test caps with threaded brass or plastic caps for long-term reliability. When a cleanout is used for snaking or inspection, ensure the cap is properly reinstalled and sealed afterward. Some homeowners install a small marker flag or record the cleanout GPS coordinates to ensure they can be found quickly during emergencies.