Symptoms of Plugged Plumbing Vents

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If you've ever wondered why your house has those pipes sticking out through the roof, they are there to help your plumbing work properly. These vents allow water to run through your pipes correctly and empty into the sewer or septic tank. But sometimes ice, leaves, and limbs or other materials plug the plumbing vents. When your plumbing vents experience this type of clogging, the problem will undoubtedly have repercussions in the home. Learn to spot the symptoms of plugged vents so you will know how to get them cleaned out and correct any problems.


The smell from the sewer or septic tank is unmistakable. This methane-laced odor seeps up through drains and in toilets to make your entire home smell like sewage. Not only is the smell gross, but it can also be hazardous to your health. If you smell this in your home, there is a good chance you have clogged plumbing vents. The lack of air pressure from the vents allows the drainpipes to empty out completely and leave p-traps dry, which opens the usual water seal that locks the gasses from the waste out of the home.

Slow Drains

If you run a bath for your children, get them out and pull the drain plug only to see the water sit seemingly stagnant in the tub and then very slowly begin to drain away, you could have plugged plumbing vents. The same goes for any slow drain in the home. The ventilation typically allows the water to rush down the pipes, but a clog could potentially affect the rate of drainage severely. Of course, you may merely have a clogged drain. If plunging, using a drain cleaning product or an auger does no good, inspecting the vents should be the next course of action.


When water goes down the drain in the sinks or showers in the home, or when you flush the toilet, there shouldn't be much noise coming from the drain once the water disappears. But if you hear a gurgling in the pipes below, you could have plugged plumbing vents. The restricted airflow from the blocked vent can cause the gurgling sound because the water and waste will be struggling to make its way down the pipe, which is usually associated with slow drains.

Empty Toilets

After you flush your toilets, the water in the tank should fill it back to the preflush level with clean water. If your toilet stays empty, it could be because there is no water in the trap and pipes below. The water from the tank simply flows down the pipe since there is nothing there to stop it at the correct level. When plumbing vents get clogged, the proper pressure is not available to keep the water where it belongs, and your toilets could end up dry because of it.


Lee Morgan

Lee Morgan is a fiction writer and journalist. His writing has appeared for more than 15 years in many news publications including the "Tennesseean," the "Tampa Tribune," "West Hawaii Today," the "Honolulu Star Bulletin" and the "Dickson Herald," where he was sports editor. He holds a Bachelor of Science in mass communications from Middle Tennessee State University.