Creative Barn Plumbing Vent Solutions
Remodeling left your toilet without a roof vent? Learn if using a cleanout junction with a wall vent is a safe plumbing solution.
When remodeling a barn or other outbuilding, plumbing venting can become a challenge. Vents are needed for toilets to flush properly and to keep sewer gas out.
In this case, an old barn remodel moved a cleanout junction from outside into the building footprint. Now the cleanout sits just inside the wall, leaving the owner to wonder: could this be used as a vent?
Question:
Can you use a cleanout junction with a 90-degree elbow through a wall to serve as a vent instead of running a vent stack to the roof?
Answer:
No. Under plumbing codes, a cleanout cannot be used as a vent. Toilets require a vent that terminates outdoors above the roofline. Wall vents like dryer vents are not allowed for toilets. This setup would not meet IPC or UPC requirements and may cause unsafe sewer gas discharge inside or near the building.
While creative ideas may seem appealing, plumbing codes are strict for a reason. A toilet without a proper vent can have weak flushes, siphoned traps, or even dangerous sewer gas issues. If a full roof stack is not possible, you may explore code-compliant options such as an Air Admittance Valve (AAV), though local code approval is required.
If you are unsure, check the International Plumbing Code venting section or consult your local plumbing inspector.
Being creative is good, but safe and code-compliant venting is always the right choice.
I’m Chris Mayer, writing for Plumbing 101.
