Drain Vent Clogged

Small rodents or birds can fall into the stack and become lodged. How to Clear a Clogged Drain Vent

But here is the dirty secret most homeowners never realize until they’ve cut a hole in their ceiling: Your drain isn't the problem. Your drain’s breath is.

Diagnosing a clogged vent often requires a process of elimination. If a homeowner has cleared the p-trap and snaked the drain line but the problem persists, the focus must shift upward. The vent stack is exposed to the elements on the roof, making it vulnerable to nature. The most common culprits of a clogged vent are environmental debris, such as fallen leaves, pine needles, or snow and ice accumulation during winter. In some cases, small animals or birds seeking warmth may nest inside the pipe, completely obstructing the airflow.

While you're up there, ensure the rubber booting (flashing) around the pipe isn't cracked, as this can cause attic leaks. Preventing Future Clogs

If only the toilet clogs, it's a poop knife problem. If only the sink clogs, it's hair. But if everything on the same floor or side of the house drains slowly at the same time? That is a vent issue. The entire branch is suffocating.

In extremely cold climates, water vapor can freeze at the top of the stack, slowly closing the opening with frost.

Respect the vent. It is the only thing standing between you and a house that smells like a petting zoo.