How To Clear Toilet Vent

Do you have plumbing problems because of a clogged vent? Find out how to diagnose and fix plumbing vent problems here.

When your plumbing vent pipe is clogged, you put yourself and your loved ones at risk.

You'll likely know it's clogged if there's a gurgling sink or foul odors inside your house. Left unchecked, sewer gasses can seep into your home to cause sickness or even lead to explosions.

Read these tips to learn how to clean and clear a plumbing vent.

What is a Plumbing Vent?

When water runs down your drains or toilets, it can fill the pipe and create a vacuum. The plumbing vent lets air above your roof enter the pipe. The air pressure then equalizes and keeps a vacuum from forming.

Water and waste will again freely flow down into your sewer line or septic system.

A plumbing vent or "stack" as the pros call it, runs from your plumbing through your attic to the top of your roof.

It's best to have your plumbing vent atop your roof to let noxious fumes leave your home above nose level.

P-traps & 'Cheaters'

In older homes, a vent may also be located under a kitchen or bathroom cabinet at a level above the p-trap.

Like the plumbing vent, a p-trap prevents odorous gas from seeping up through a toilet, sink or floor drain. It's the U-shaped piece of pipe beneath your sinks and behind the toilets.

While relying solely on a p-trap isn't ideal, it does usually keep a vacuum from forming.

If you don't see a plumbing vent poke up through your roof covering, an interior vent or "cheater" vent may have been installed. A "cheater" is a one-way vent installed after the trap on the drain line of a toilet or sink. Building codes often prevent its use because of ineffectiveness.

Is Your Vent Clogged?

There are several ways to tell if your plumbing vent is clogged. Even if there's not a complete blockage, if you notice any of the following, inspect your plumbing vent pipe or contact a professional to assess the situation.

When you flush your toilet, do you hear sounds from your bathtub or sinks?
Do you notice a rotten egg smell in your bathroom or kitchen?
Do your kitchen or bathroom sinks gurgle when they drain?

How to Clean and Clear Your Vent

Climb onto your roof. If it's too steep or slippery due to weather, call a professional.
Have an assistant flush a toilet while you hold your hand over the vent. If you don't feel suction, the line is blocked further down.
Use a plumber's snake of electricians fish tape to unclog the stoppage.
If you can't entirely remove the clog with your "snake," use a garden hose to flush out remaining debris.
Have your assistant flush the toilet again while you hold your hand over the vent to feel for suction.

If you still have issues, contact a professional.

Clear Vent from Inside

If climbing onto your roof is "below your pay grade," you can also clear a vent from inside your attic. You need enough room to access your vent pipe, which must be PVC, not cast iron.

PVC is the white plastic pipe commonly used for plumbing and drainage. PVC stands for polyvinyl chloride, and it's a common replacement for metal piping.

Locate the section of your vent above your bathroom or kitchen. Cut away a large enough piece of the PVC pipe to run a plumbing snake downward. A hacksaw makes quick work of the pipe.

Run the snake downward until you find the clog. If the blockage is wet leaves or an animal, it's possible the clog is above you. If so, just run the snake upward.

To repair the vent's PVC pipe, you can use rubber or PVC couplings with cement to bridge the part you removed. The vent is often loosely attached to the roof with a flexible rubber gasket so it can be shifted up or down to make this re-fit easier.

Keep Your Vent Clear

If your plumbing vent pipe gets clogged regularly, there may be other factors involved.

Clear Debris

If tree branches hang over your roof, trim them back. When wet leaves and other debris get stuck inside your vent pipe, it doesn't take long before there's nowhere for the air to go.

Keep Out Vermin

Birds, rats, chipmunks and squirrels may enter your plumbing vents. Whether they get stuck, build a nest or leave unwanted by-products, it's very possible they'll block your vent.

Improper Vent Cap

It may seem like a good idea to cap your vents to keep animals and leaves out. But the wrong vent cap can actually create the problem you want to avoid. In cold weather climates, a vent cap can create an ice barrier atop your vent.

Vent Pipe Too Small

If regular maintenance like pest control and tree-trimming still aren't enough to keep your lines clear, your vent pipe may not be large enough for all of the drains running to it. You may need a wider stack.

In some areas, plumbing codes call for a 4-inch-wide pipe to handle a kitchen and multiple bathrooms. If all of your plumbing runs through a single 2-inch stack, it may not be enough to vent all your fixtures properly.

Upgrading your stack requires a professional to assure the upgrade meets local code.

Don't Put Yourself at Risk

Don't let a clogged plumbing vent put your family at risk. Especially when the solution is so simple.

Just follow the steps above to clean and clear a plumbing vent and your troubles should disappear straight down the drain.

Don't put yourself at risk if there's a more significant problem or if scrambling across your roof seems dangerous. Call the qualified professionals at Eyman at (402) 731-2727 to handle your plumbing issues.