Basement Smells Like Skunk? (Possible Causes & Fixes)

Ossiana Tepfenhart
by Ossiana Tepfenhart

We all know what a skunk smells like, and it can be unnerving to notice the foul odor in your basement. The distinct smell of a skunk is off-putting and is enough to confuse any homeowner when it’s in your house. So, why does your basement smell like skunk?

A clogged sewer vent can cause sewer gases to back up and make your basement smell like a skunk. Skunks can get stuck in your basement and spray thiol which is the foul liquid that they produce. Sewer gas can emit from your basement floor drain and make it smell like a skunk or rotten eggs.

Contact a professional if you find evidence that there is a skunk in your basement. Unclog your sewer vent with a drain snake or garden hose so that sewer gases don’t leak into your home. Follow along as we explore what you can do when your basement smells like skunk.

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Basement Smells Like Skunk

It can indicate an emergency if your basement smells like a skunk in some cases. That is why it is important to diagnose the problem right away to mitigate any risk. Let’s take a look at the main causes and solutions to a basement that smells like a skunk.

Skunk in Basement

A skunk can enter your home through a weak point and stay in your basement. This will cause your basement and possibly the rest of your house to smell like skunk. Skunks spray their noxious liquid known as thiol when they feel threatened.

It is easy to understand why a skunk would be fearful in a strange environment and spray thiol. Thiol smells strong and it is difficult to eliminate the odor from your basement. This liquid is harmful to humans and can injure your eyes or nose and cause stomach problems.

Contact a pest control service if you find evidence of a skunk in your basement. They are best equipped to remove the animal without harming it. Set out bowls of white vinegar in your basement and air it out once the skunk is gone to remove the odor.

Sewer Gas

Sewer gas can explain why your basement smells like skunk. The mixture of methane and other gases within your sewer line can produce an odor similar to a skunk or rotten eggs. Sewer lines contain hydrogen sulfide which grows stronger when there is rotting animal or plant matter.

Skunky odors can escape your sewer lines and emit from your basement floor drain. Call your municipal sewer waste company if you notice a sewer gas leak. The gases within a sewer such as methane can combust, so it’s important to contact a professional right away.

Skunk Cabbage

Skunk cabbage is a plant that produces a foul odor similar to its namesake animal. This plant can cause your basement to smell like skunk, particularly if it is near your basement windows. You can reseal the windows so that the odor doesn’t enter your basement and stink up the house.

Otherwise, the best course of action is to dig up your skunk cabbage plant. This is ideal because while some homeowners like the plant, it can cause your house and yard to smell like a skunk.

Clogged Sewer Vents

Sewer vents can clog and cause your basement to smell like skunk. Other odors such as rotten eggs can also fill your basement and home if the sewer vents are clogged. You can clean the sewer vent on your roof with a drain snake and garden hose.

However, it is risky because of the height, so it is ideal to have a helper or hire a professional. Clogged sewer vents create a safety risk besides the foul odor, so it’s important to do it right away.

Poorly Assembled Plumbing And Venting

Sometimes, it’s more of a matter of wear and tear. Bad plumbing can cause leaks in a number of different ways, including:

  • A Loose Toilet Ring. Got a basement bathroom? Check to see if the sewer gas isn’t coming from a toilet that is no longer firmly secured to the floor.
  • Clogged Vents. Cloggy vents will end up blocking sewer gas passage to places outside of the home. If your sewer vents get too clogged, the gas will end up piling back up into your basement. Unclogging the vents can help.
  • Burst Sewer Lines. Let’s just hope that your sewer lines do not have a leaky line. This can happen in the walls, underneath your floor, or out in the open. If it happens, you will have to fix the line and also replace most of the stuff around the spillage. I mean, it’s going to be tainted by literal fecal matter.
  • A Foul Ejector Pit. If you have an overhead sewer line, then you have an ejector pit. It needs to be properly sealed and ventilated. If there’s no lid, loose parts, or a clog, you will need to address this.

In most cases, having poorly assembled plumbing and venting suggests that a call to a professional plumber. While these can be fixed on your own in most cases, dealing with sewer gas can be a bit too much for sensitive noses. Besides, it can really help figure out how much more stuff you have to deal with.


Though it’s not the most common way to describe a moldy smell, there are a handful of mold species that can cause a skunky, musty scent. If you notice brown or green residue in your basement, it could be the patch of mold that is making that smell. Spraying the area down with bleach is a good way to fix it or removing mold off wood using one of our methods.

Is A Skunk Smell In The Basement Dangerous?

As you can tell from our introduction, a skunk-like aroma could be a sign of something serious going on in your home. That’s why we tell you that you should err on the side of caution and assume that your odor is a gas leak if you have even the slightest hint of it being natural gas.

However, a natural gas leak isn’t the only potentially risky issue you can have. Mold can cause allergic reactions, sewer gas can actually cause serious breathing issues over time, and of course, skunks are pretty dangerous. I mean, they’re cute, but there’s a chance that they could have rabies.

Should You Call A Professional?

Professional help is always a good idea when you can’t figure out the cause of the odor on your own. In many situations, it can be hard to find a sewer line break or even trying to figure out if you need help with ventilation. Moreover, it’s not always easy to fix things once you actually do find the cause.

If you ever feel like you are not capable of handling the burden that comes with trying to track down the source of the smell, it’s best to call a pro. With that said, there are a couple of moments that you need to call someone other than a typical pro:

  • If a skunk is in your home, call animal control first. Technically, this is a public health issue first. You don’t know if it’s rabid or not.
  • If it’s a gas leak, call 911. Once again, take all living beings out of the house with you.
  • If you have a sewer break underneath your basement floor, you might need to call a public works company. First, check with a plumber to see if it’s something they are allowed to fix. If the line is outside of your home or adjacent to it, it’s probably a public works issue.

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Ossiana Tepfenhart
Ossiana Tepfenhart

Ossiana Tepfenhart is an expert writer, focusing on interior design and general home tips. Writing is her life, and it's what she does best. Her interests include art and real estate investments.

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