6 Reasons Your Carpet Smells—and How to Remove the Odors

Pet Accidents

Anyone with a furry friend knows that accidents in the home are inevitable. But when they happen on a carpet they pose a particular challenge, as urine can soak through the carpet fibers and padding, reaching the subfloor. “If not properly treated, pet urine can cause a very unpleasant and pungent odor that lingers long after drying,” cautions Faherty. "To completely remove the offensive odor, you must eliminate the odor-causing bacteria at every layer."

Faherty recommends this DIY solution to rid your carpet of pet accident stains and smells:

1. If the accident is fresh, blot the area with a clean towel to remove as much moisture as possible.
2. To neutralize the bacteria, apply a 50/50 solution of vinegar and water. Make sure to use enough of the solution to treat all the affected layers.
3. Allow the solution to sit for 15 to 20 minutes.
4. Remove excess moisture with clean towels or suction.
5. Circulate air to dry the area completely.

For particularly persistent pet odors in your carpet, a store-bought enzymatic cleaner might be needed to break down and eliminate the odor-causing bacteria. Always make sure to use caution and follow the product’s label instructions for safety.

Food and Beverage Spills

Accidental food and drink spills on a carpet are as predictable as the dawn. While water can be blotted up quickly without much worry, soda and wine are a whole different ball game. The same goes for food: a few crumbs can be dealt with by a quick vacuum over the spot, but lasagna and salad dressing create a different kind of challenge.

Faherty explains that the “proteins left behind in food and drink spills can serve as nourishment for bacteria, which ultimately cause odors.” He recommends addressing the spills quickly with this effective DIY solution before the odors have a chance to develop:

1. Immediately remove all particles and blot the affected area with a clean towel to remove as much moisture as possible.
2. Apply a spray mixture of warm water, mild dish soap, and hydrogen peroxide to the spot. 
3. Remove any remaining moisture with a clean towel or suction.
4. Circulate air to dry the area completely. 

Pro tip? For optimal moisture removal, place clean towels over the freshly treated area, weigh them down with a heavy object, and let them absorb for several hours.

Mold

Spills, leaks, and high humidity can all be the culprit behind mold developing in your carpet. “One of the major causes for smells in your carpet is moisture, which gets trapped in the fibers and padding, harboring the growth of mold and mildew,” explains Luis Toja, carpet and upholstery cleaning expert at Fantastic Services. Not only can mold be the harbinger of bad smells, it can also pose a health risk to the home's inhabitants.

To remove a musty odor caused by microbial growth, Faherty recommends using the following method:

1. To create a drier environment, begin by ventilating the room and circulating the air. Open windows and floor fans are your friends.
2. Sprinkle baking soda directly onto the affected area and gently work it into the carpet fibers with a stiff brush to ensure it reaches the base.
3. Let the baking soda sit for several hours, then vacuum thoroughly.
4. Follow this by applying a mixture of 50/50 water and vinegar. 
5. Remove any excess moisture with a clean towel and allow the area to dry completely.

Be mindful of safety considerations and wear protective gear. To ensure there is no cross-contamination, treat all equipment used (brush and vacuum) with hydrogen peroxide immediately after use.

Smoke and Cooking Smells

If you have come by your carpet by way of thrifting or inheritance, have hosted friends who smoke, or have ever smoked yourself, you may have stale smoke odors dwelling deep within your carpet fibers. “Smoke has tar and other residues that build up in the carpet,” says Faherty. The same applies to cooking smells, which can linger in the household and make a home in your carpet. 

Faherty recommends evenly sprinkling your carpet with baking soda (one small 16-ounce. box covers roughly 400 to 500 square feet), which absorbs any byproducts from smoke and cooking. Let the baking soda sit for at least two hours, and then thoroughly vacuum. The vacuuming process will also assist in removing the odors. 

For deep-set odors, try evenly misting 3 to 5% hydrogen peroxide over the entire carpet, making sure to avoid furniture and any non-carpet surfaces. Blot any moisture with a clean towel or suction vacuum. Circulate air until completely dry.

Off-Gassing From New Carpets

New carpets can emit fairly offensive odors for some time after their initial installation. Rather than live with it for the duration, you can take care of this smell by spraying a solution of three equal parts vinegar, water, and baking soda lightly over the area and allowing it to dry thoroughly.

Lightly brushing the carpet with a nylon brush is the next optional step, then finish by giving your new carpet a thorough vacuum. The chemical smell should be gone, leaving your house smelling fresh.

Age

Whether from age or neglect, occasionally, there is a carpet odor without an obvious source. In this case, you’ll likely need professional carpet cleaning help. In this case, Toja recommends either renting a commercial carpet cleaner or hiring a professional carpet cleaning service. It’s critical to perform this type of carpet cleaning correctly to prevent the odors from worsening, he cautions.

Finally, there may come a time when a particularly obstinate smell will resist even your best efforts. Only then do you need to consider replacing your carpet entirely.