Why Is There a Strange Sewer Smell in My House?

No matter how clean your house is, strange and unwanted odors can still sometimes creep into your living space. And a strange sewer smell is an example of that.

When it comes to things like this, it’s imperative to follow your instincts and look for their source.

Where could this smell be from? Let’s find out.

What’s the Reason Behind the Strange Sewer Smell in My House?

Why Is There a Strange Sewer Smell in My House?

A strange sewer smell in houses can stem from a variety of reasons. Let us explore some of the primary causes that may result in this issue.

1. Mildew and Mold

The presence of mold and mildew in your home may, strangely enough, emit an unpleasant odor.

Whether it is in the basement, kitchen, or bathroom, mold and mildew build-up can cause a sewer, pungent fragrance, or a sewer sticky smell. 

Mold and mildew result due to the presence of water, fluid, and moisture in certain areas of your home.

The scent of mold and mildew may seem sewer-like and unpleasant, which can be harmful to your health and hygiene.

2. Refrigerant Leakage

A sewer odor in your home may also result from a refrigerant leakage situation. Refrigerant is a substance that aids in the proper operation of a refrigerator. 

If your refrigerant leaks, it can give off a strange sewer scent.

If the leak is not fixed immediately, it can lead to serious medical problems as the refrigerant contains some hazardous components.

3. Air Conditioner Leakage

Like refrigerants, air conditioners too come with a liquid that helps aid proper function. If this air conditioner liquid escapes, your house may smell sewer and maple syrup-like. 

Air conditioning leakages occur when formic acids from various parts of your home combine with the copper in your air conditioner.

4. Furnace Leakage

Another source of a sewer scent circulating your home could be a leaking furnace. 

In most cases, the heat exchanger in the furnace pumps hot air via the air ducts. If it spills, it will emit an unpleasant, formaldehyde-like smell. 

However, unlike the other reasons, this sewer smell is out of the ordinary, potentially signifying a threat that must be addressed right away.

Carbon monoxide is a toxic gas that may leak from heat exchangers.

While carbon monoxide does not have a distinct smell, it can occasionally give off an unpleasant sewer odor. 

If your heat exchanger starts to give off a sewer smell, shut it down immediately and get it looked at by a professional.

5. Insect Infestation

It may sound strange, but an insect infestation can also result in a sewer smell in your home. In general, bugs or insects that can generate sewer oil emit a sewer scent. 

A sewer odor can indicate a bug infestation, such as ants, bedbugs, cockroaches, etc.

If you come home after a vacation and detect a sewer smell, be sure to consider a possible insect infestation.

6. Plumbing

If you’ve ever wondered why your house smells like a sewer, there’s a strong possibility that it’s due to your plumbing system.

Over time, small cracks and leaks can develop in the pipes, allowing sewage and other waste products to seep into your home. 

In addition, tree roots can grow into the pipes, causing blockages that can lead to backups.

If you suspect that your plumbing is the cause of the sewer smell, it’s important to have a professional take a look at it as soon as possible. 

While a repair may be necessary, catching the problem early can help to prevent more serious damage from occurring.

7. Basement Drain

Homes with basement drains are particularly susceptible to this issue, as the drain can become clogged with debris and cause sewage to back up into the house.

In addition, the drain may not be properly vented, allowing sewer gasses to escape into the basement. 

If you suspect that your basement drain is causing a sewer smell in your house, contact a plumber to have the issue addressed.

In most cases, a simple drain cleaning will be all that’s needed to eliminate the problem. 

However, if the drain is severely clogged or improperly vented, more extensive repairs may be necessary.

With a little investigation, you can quickly identify and resolve the source of the sewer smell in your house.

8. Lack of Air Circulation

This is a rare occurrence, but a sewer smell in your home can result from reduced air circulation.

This is typically the case when you come home after a vacation and encounter a faint sewer smell diffused in your home. 

When you go on vacation, your house does not receive enough ventilation and air circulation.

Consequently, you may notice a sewer odor when you return home. In general, this odor does not linger around for long.


How can you get rid of the sewer smell from your home?

If you know the root cause of the issue, you can direct your eradication efforts accordingly to get rid of the smell.

What to do if the smell is due to molds?

If the sewer odor is the result of mold and mildew build-up, you must clean them to eliminate the smell. 

Clean any areas that are exposed to persistent wetness like the kitchen, bathroom, and basement, for example.

Cleaning carpets, rugs, mats, and other such items can also be beneficial.

How to fix refrigerator and air conditioner leaks?

To address a refrigerant or air conditioner leak, it is best to seek expert assistance.

How to deal with a furnace leak?

If you suspect a furnace leak, get professional assistance right away and evacuate your home because carbon monoxide leakages can be very dangerous.

How to get rid of pest infestation?

In most cases, bed insect infestations can be resolved by washing the bedsheets in warm water.

Furthermore, you can use vinegar or commercial remedies to repel mosquitoes or bugs.

If you suspect a massive infestation, however, seek professional assistance.

Can I fix the ventilation problem?

You can remedy a ventilation problem by ensuring that the house has adequate ventilation.

Open the house’s doors and windows and switch on the fans to allow air circulation.

I am experiencing chemical odors. What to do?

If you notice other gasses or substances that have a sewer fragrance in your home, you should seek professional help because you may not be aware of how hazardous the fumes or chemicals are.

Final Thoughts

Sewer smells are never pleasant. It makes people feel disgusted, sometimes even to the point of puking.

Your home is the place where you and your family should relax, so it’s important to get rid of this unwanted smell once and for all.

We hope the eight causes discussed above help you in identifying the cause of this matter. Finally, you can remove the smell and/or purify the air more effectively for a totally odor-free home.