What’s That Smell? Dealing with Sewer, Pet, Mold and More

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The smells around our homes all tell a story. Some are very pleasant, such as a fragrant springtime blossom; other odors might be a sign that something is amiss!

What Smells of Danger!

Smoke!

Any smoke indicates a potentially dangerous condition exists somewhere in the house. Locating the source is an action step you could take only when the smoke is not overwhelming. If you see smoke, you and your family likely need to evacuate the house quickly and call 911 immediately. If you do not have training as a Firefighter, this isn’t the time to start.

You might poke around for a source if you sense an acrid odor but see no source or smoke. Your olfactory senses take the lead here as you walk around sniffing your way through the house. The source of the smell could be hidden in the walls, so touch them carefully to see if the surface feels warm. If you see the surface blistering, leave and call 911. Don’t open the wall, as that will add oxygen to the fire source and will make matters worse.

Keep your up-to-date quality household fire extinguisher with you as you search.

Gas!

Natural gas and propane gas have a chemical added to them that resembles a quite pungent rotten eggs smell. If you find it hard to breathe, leave. Call 911. Be safe.

1. If you smell gas and breathing is not the problem, check typical sources such as pilot lights for stoves, ovens, water heaters, and furnaces to be certain they are lit. A lot of newer appliances have an electronic started where a pilot light is not needed. Be sure you know what you have so you know where to look.
2. If you are missing your sense of smell, invest in gas detection units to monitor the gas in your home. Southwest Gas offers a booklet on detecting a leak using your sense of smell, sound, and observation.
3. Turn off all valves that distribute gas in your home. The main shut-off should be accessible where the gas line entering your house is near the meter. If you have a propane tank, there is a shut-off at the tank.
4. Open all your doors and windows to clear the gas out.
5. Call the fire department to help locate larger leaks. Your gas supplier can also help.
6. SHUT DOWN ALL OPEN FLAMES! Did we say that loud enough? Even a small candle can spell disaster.

Mold and Musty Smells

That musty smell you are detecting may be from mold growing in hidden areas. Mold detection is an important step. Mold can lead to many health hazards, primarily respiratory.

1. Look for damp areas on walls and floors, particularly carpet. Peeling paint or surface blistering may be a telltale sign.
2. Look for dark, fuzzy-like growths. That is mold.
3. You can clean up small areas of mold with soap and dishwashing detergent, but cleaning specialists warn against using bleach except on non-porous surfaces like shower doors and tile. Bleach can cause the spores to multiply. https://rosieonthehouse.com/diy/how-can-i-clean-mold-when-i-see-it/.
4. If you find mold and someone in your home is allergic to molds, use a restoration company to abate the problem. Restoration companies will work to remove the mold and inhibit its return.

Obnoxious But Not Deadly Smells

A real common source of household odors is sewer gas smells. There are several reasons why you are getting these odors. Some are easy to fix, and others can take a bit of expertise and special equipment to mitigate the source. Improper venting of sewer lines is the primary cause.

• Roof Vents – Over the years, we have found a common denominator for venting problems. Roof vents may not be high enough off the roof surface. Parapet walls, chimneys, or roof-mounted equipment could also block vents. These situations prevent proper air circulation around the vents to draw out the sewer gasses. When the vents are not tall enough, the gases tend to curl down the roof and under the eave, allowing the gas to enter your home through windows or even soffit vents.

Remedies include:

1. Adding 6″ to 8″ of additional pipe to the vents making them taller.

   

2. If that doesn’t work, other remedies include introducing a fan and filter system on your main vent pipe or several vent pipes. These systems are like the type used in radon gas mitigations. A company called Odor Hog makes a product that installs on a vent pipe, draws air out of the pipe, passes that air through a filter, usually charcoal activated, and then the odorless air passes to the atmosphere.

Other Odor Sources

Sewer gas isn’t the only common household odor. Others include:

• Pet Smells- The most pungent of these is usually urine odors from a pet, particularly the feline variety.
  • Carpeted floors are the most expensive remedy, as urine will soak through the carpet into the pad below and through the pad onto the subfloor. Often, the carpet and the pad will need to be replaced.
  • Treatment of urine that has soaked into the concrete or wood surface below must be treated to mitigate the odor. Choose a cleaning product that has enzymes designed to remove pet odor and follow the directions on the bottle. It may take several treatments. Let the sub-surface completely dry before covering it with tile or carpet.

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  Garbage disposal- The gasket at the sink is typically the source of odors here. Keeping the underside of the gasket clean will prevent those nasty smells. If the gasket is not removable, unplug the disposal and reach in to clean the rubber on the underside.

• Laundry- there are stubborn smells that are hard to remove from laundry. We like Enzyme Laundry Booster to rid laundry of lingering odors.

How To Find the Source of Difficult Odors.

Over the past few years, odor detection science has made great leaps. There are lots of testing procedures; however, two of our favorites are the canister and smoke tests.

1. Canisters – A vacuum canister is placed in your home for about a week with this relatively new service This device sucks in air about every two seconds over the course of the week. The device registers all manner of odors in the air. If you put this device in your kitchen for a week, it will tell you the kind of perfume that has been used in the master bathroom. The information is analyzed, and once the source of the odor is isolated, a proper mitigation procedure can be designed.
2. Smoke – This process involves injecting smoke under high pressure into the vent stack. The smoke escapes through cracks and reveals where those nasty smells are coming from.

There are lots of sources for those nasty smells around the home. We dug up one of our previous articles that addresses even more issues than we did here. https://rosieonthehouse.com/diy/how-can-i-prevent-indoor-odors/

After reading these articles, we would love to hear about your strange stories. Send them to info@rosieonthehouse.com/.

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PODCAST

March 1st, 2025

The smells around our homes tell a story. Some are very pleasant, such as a fragrant springtime blossom. But other odors might be a sign that something is wrong. From smelly sewer type odors to smoke, the rotten egg smell of gas, mold, even laundry and garbage disposal smells. Its a stinky topic but we have some solutions to smell good again!

Original Broadcast Archive Page With Expanded Content

PHOTO CREDIT

• IStock
• OdorHog
• Rosie on the House