Can Your Plumbing Vents Clog? (Hint: Yes, They Can)

26 January 2023
 Categories: , Blog


Have you ever tried to pour liquid out of a can or container that just has one small hole in it? The liquid comes out very slowly until you punch a second hole. This is because air needs a way to enter the container and displace the liquid as it flows out. Your plumbing system is set up similarly; it has vents so that air can escape the pipes as wastewater flows through them. So, that might leave you wondering, can those vents become clogged? Indeed, they can. Here's a closer look at what causes plumbing vents to clog, how to recognize this issue, and what you can do about it.

What causes plumbing vents to clog? 

The clogs that appear in plumbing vents can come from one of two places: the pipes or outside. Sometimes, something from the outside will fall down the vent. This can be snow, leaf debris, or even a bird's nest. Other times, waste traveling down the pipe will rise up into the vent stack, get caught, and clog the vent. This often occurs when you have a partial blockage in your drain lines themselves. A partial blockage slows down the rate at which waste moves through the pipes, which gives some of it more time to rise into the vent stack.

How do you know your vents are clogged?

Once you become aware of the signs of a clogged vent, they are hard to overlook. Most notably, your drains will slow down since air will have a hard time escaping from the system to make room for the water. You may also notice foul odors coming from your drains. This is the air that should be going up the vents leaving the pipes the only other way it can—through the drains.

What can you do about clogged vents?

Call your plumber. This is a fairly routine problem for them to fix. They'll generally start by sending a camera down into the vents to locate the clog and assess its size. Then, they will remove the blockage, either by pulling it up the vent stack or by washing it down with a powerful jet of water.

Clogs in the plumbing vents are unfortunately common. Luckily, they are also fairly easy for a plumber to address. Now that you know they can occur, keep your eyes out for signs of a clogged plumbing vent so you can seek repairs ASAP when needed.

Contact a local plumbing service to learn more.