What Are the Common Reasons Behind Plumbing Odors?

If your kitchen sink suddenly becomes nauseating or your toilet has a weird, funky smell, the problem may be bigger than you thought. The smell may be a plumbing concern if you regularly clean your house, kitchens, and bathrooms. 

Many plumbing odors are beyond your control, and it is always better to seek professional help when it comes to this matter. Here are some of the most common causes of plumbing odors:

1. Blocked Drain Vents

Drain vents are found at the top of your roof, helping maximize sewer gas pressure in the wastewater system. It keeps pipes healthy and prevents sewer gas from entering your home. A properly working system means the drain vents push these gases beyond your water sources and out to the roof.

Your odor concern may stem from this system. If the drain vents get clogged due to snow and animal nests, unpleasant smells are blocked from the vent and come up through the drain. 

2. Drain Issues

Drains are one of the most common causes of plumbing odors in kitchens and bathrooms. These usually occur because of several reasons. To properly address your concern, it’s best to have a professional check your drains.

3. Sewer Line Problems

If odors persist in more than one sink and, instead, in most sinks in your house, including bathtubs and showers, it’s an indication of a more severe problem. The issue may no longer lie with your drain vents but in the sewer line. One of the signs of a compromised sewer line is hearing unusual noises near drains, such as loud gurgling.

The only way this issue could get resolved is if a professional is involved. There might be a break in the sewer line transporting wastewater to the sewer system. 

4. Damaged Seal

Every toilet is sealed with a wax ring underneath. It affixes the toilet to the floor, preventing odors and leaks. However, wax doesn’t last a lifetime, and the ring is expected to loosen or break after some time. 

If that is the cause behind your problem, the air and water in the corresponding pipes are fighting for space. Air and noxious sewer gas are forced back up and into the room, hence the odor problem your home is having. You can solve this issue by having your toilet resealed with a new wax ring.

5. Dry P-Trap

Every sink has a drainage system and a curved pipe underneath called a p-trap. The p-trap holds water in the curved bend below the sink to seal out sewer gases that would otherwise enter your home. 

If the sink is unused for several days, the p-trap could dry up and escape sewer gases and odors. To get rid of the odor, run water down the drain for a minute or two. You can also mix vinegar and baking soda to get rid of the smell for sure.


Plumbing odors are a household problem that you want to address quickly and properly. The odor can be nauseating and can also pose health problems, so resolving the issue at hand immediately should be your top priority. It’s best to consult a professional once any of the issues above arise. 

Professor Plumb is a veteran-owned plumbing company in Columbiana, AL that has been providing professional plumbing services for more than 20 years. Whether you have a clogged drain, a leaky faucet, or a new water heater to be installed,  we have a solution for you! Call us at (205) 671-5049 today.

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