2023 Guide: Mildew Smell After Carpet Cleaning – How to Eliminate It

If you have recently had your carpet deep cleaned and now you notice a musty and unpleasant smell, you are not alone. One of the main reasons for the mildew smell after carpet cleaning is due to the underlay.

Because the underlay is not directly exposed to light or air, it takes longer to dry and excess moisture can lead to the growth of mold and mildew, resulting in an unpleasant odor that can be frustrating for homeowners.

Are you tired of the unpleasant odor coming from your carpet after cleaning? Check out this Youtube video: “How to Remove Mildew & a Musty Smell From Carpet” and learn the easy and effective solution to eliminate that mildew smell.

The Science Behind Mildew Smell After Carpet Cleaning

After deep cleaning, carpets might smell different due to excess moisture. This is because the carpet padding, specifically the underlay, takes longer to dry as it is not exposed to direct light or air.

The longer drying time and excess moisture create an environment for mold and mildew to grow, leading to an unpleasant mildew smell after carpet cleaning.

In addition, carpets also absorb moisture from the air during periods of high humidity. This causes odors, such as smoke, to become trapped within the carpet fibers.

If moisture seeps into and below the carpet, mold and mildew growth can occur, intensifying the unpleasant smell.

To prevent mildew smell after carpet cleaning, it’s important to ensure proper drying and ventilation of the cleaning area. It’s also recommended to regularly clean and maintain carpets to prevent the buildup of excess moisture and mold growth.

Why Proper Drying is Important

After a deep carpet cleaning, it is essential to allow proper drying to prevent moisture build-up, which can lead to the growth of mold and mildew. Excess moisture is a breeding ground for these microorganisms, and it can result in a musty and damp smell.

The underlay of the carpet is one of the areas where moisture can hide because it does not get proper sunlight or ventilation. The longer it takes to dry, the higher the chances of mold and mildew growth, adding to the unpleasant odor.

In addition to this, carpets also absorb moisture from the air, leading to airborne odors like smoke that can become trapped in the carpet fibers. Once trapped, they can contribute to making the carpet smell.

If moisture gets into the carpet and below, it can encourage mold and mildew growth, leading to a musty odor. It is advisable to use proper drying techniques after cleaning to prevent these occurrences.

Proper drying techniques are necessary to prevent your carpet from smelling bad. Take extra precautions, especially in areas that are prone to high humidity.

Common Reasons for Mildew Smell After Carpet Cleaning

Low-quality carpet cleaning

One of the most common reasons for a mildew smell after carpet cleaning is using low-quality carpet cleaning equipment and products. If the cleaning solution and equipment used are not powerful enough, it may leave behind excess moisture which can cause mold and mildew growth.

This is why it is important to choose a reputable carpet cleaning company that uses high-quality equipment and products to avoid any unwanted odor after cleaning.

Drying problems

Another common reason for mildew smell after carpet cleaning is drying problems. If the carpet is not dried properly after cleaning, excess moisture can seep into the carpet fibers and underlayment.

This can create the perfect environment for mold and mildew to grow, which leads to a musty odor. It is crucial to use proper drying methods such as high-powered fans, open windows, and dehumidifiers to ensure the carpet dries completely and avoid any mildew smell.

Persistent stains

If a stain is not properly cleaned during the carpet cleaning process, it can lead to a bad smell. Old or tough stains can trap bacteria and other odor-causing particles underneath the carpet fibers, leading to an unpleasant odor.

It is important to address any stains before cleaning to ensure they are removed completely, avoiding any possible odor issues later on.

Other common reasons for a bad carpet smell

Aside from the above-mentioned reasons, there are other common reasons for a bad odor in carpets such as pet odors, cigarette smoke, spills, and high humidity levels. If the carpet is exposed to any of these factors, it may cause unpleasant odors that may linger even after cleaning.

It is best to address these issues promptly to avoid any odor problems in the future.

What To Do and Not Do When You Have A Smelly Carpet

If you’ve recently deep cleaned your carpets but the mildew smell remains, there are a few things you can do to eliminate the odor. However, there are also some actions that you should avoid.


  • Use natural cleaning agents like white vinegar and baking soda which can help eliminate the mildew smell.
  • Ensure that your carpet is completely dry after cleaning as moisture can lead to further mildew growth.
  • Vacuum your carpet regularly to prevent dirt and dust buildup which can trap odor-causing bacteria.
  • Get your carpet professionally cleaned annually to ensure deep cleaning and prevent the buildup of odor-causing agents.


  • Ignore the mildew smell as it can alert you to potential mold growth which can be a health hazard.
  • Use harsh chemicals as they can damage your carpet and worsen the smell.
  • Place heavy furniture on a wet carpet after cleaning as it can prevent the carpet from fully drying out and lead to mildew growth.

How to Get Rid of Mildew Smell After Carpet Cleaning with Vinegar

If you want to eliminate mildew smell after carpet cleaning naturally, vinegar can come to your rescue. It’s also an affordable method to get rid of the odor.

Here’s how you can use it:

  1. Mix one cup of white vinegar and warm water in a spray bottle.
  2. Spray the solution on the smelly carpet area and give it some time to soak in.
  3. Rinse the area with water.
  4. Let the carpet air-dry completely. Note: Don’t walk on the damp areas as it can spread mildew instead of eliminating it.

If the smell persists, repeat the process until it disappears altogether.

How to Remove Mildew Smell After Carpet Cleaning with Baking Soda

Another natural method to eliminate mildew smell after a carpet cleaning is to use baking soda which is an old-school and efficient solution.

Here’s how you can use it:

  1. Sprinkle baking soda liberally over the entire smelly carpet surface.
  2. Gently rub the baking soda into the carpet fibers using a soft-bristled brush.
  3. Let it sit for a few hours or overnight.
  4. Vacuum the carpet thoroughly to remove the baking soda residue.

Baking soda is a natural odour absorber and therefore is effective at reducing mildew smell. This method is ideal for people with pets and young children who may not want to use chemicals or have respiratory allergies.

Other Solutions for Removing Bad Carpet Smell

If you’re not a fan of natural remedies, there are other ways to eliminate mildew smell after a carpet cleaning.

Here are some options:

  • Buy an air purifier which can eliminate airborne bacteria causing odours.
  • Use enzymatic cleaners that break down odor-causing bacteria instead of just masking the smell.
  • Replace the carpet padding which can trap moisture and lead to mildew growth.

Remember, the best way to prevent bad carpet smell is to ensure proper and regular cleaning of your carpets and to avoid excess moisture buildup.

Pro-tip: Avoid using too much vinegar or baking soda as it can damage your carpet fibers.

What If Nothing Works?

If the mildew smell after carpet cleaning persists and none of the DIY solutions seem to work, it might be best to consider hiring a professional. Professional carpet cleaners have more advanced equipment that can thoroughly clean deep into the fibers and underlay, effectively eliminating any persistent odors.

Moreover, they have experience dealing with various types of carpet and different forms of odors, so they can handle even the toughest of smells. They can also provide specialized treatments that can prevent mold and mildew growth in the future, ensuring a fresh-smelling and hygienic carpet for longer.

While it may cost more than DIY solutions, hiring a professional can save you time, effort, and provide guaranteed results.

Preventing Mildew Smell After Carpet Cleaning

Carpet cleaning is important to maintain a healthy and fresh living space. However, one of the major problems that come after carpet cleaning is the mildew smell.

The odor can be unpleasant and uninviting. Here are some tips to avoid it:

Proper Drying

After deep cleaning, make sure to dry the carpet thoroughly to avoid trapping excess moisture. Use fans, open windows or doors, or run the air conditioner to speed up the drying process.

Elevated humidity levels can cause mildew, so ensure the room is adequately ventilated.

Regular Cleaning

Regular cleaning is essential to prevent odors and buildup of dirt and moisture. Consider vacuuming your carpets at least twice a week, especially in high-traffic areas.

Spot clean any accidents immediately to prevent stains and odors from setting in.


Using a dehumidifier can lower the humidity levels in your home, which will prevent mold and mildew growth. An ideal humidity level should be between 40-50%.

Be sure to empty the dehumidifier tray regularly to avoid buildup that can cause odors.

Vinegar Solution

Vinegar has a natural deodorizing and cleaning effect that can help get rid of mildew smells. Mix equal parts of water and white vinegar in a spray bottle, and spray the solution on your carpets.

Allow it to sit for 10-15 minutes, then blot with a clean towel. Repeat if necessary.

Professional Cleaning

Having your carpets cleaned professionally can ensure that all dirt, dust, and moisture are removed properly. Professional cleaners have the right equipment, expertise, and cleaning solutions to get the job done effectively.

Schedule a regular carpet cleaning service to keep your carpets fresh and odor-free.

Note: If you notice any mold or mildew growth on your carpets, it’s best to contact a professional cleaning service immediately. Mold can cause serious health problems, especially for people with allergies or respiratory issues.

By following these tips, you can prevent the mildew smell after carpet cleaning and maintain a healthy living environment. Proper maintenance and regular cleaning are crucial for keeping your carpets fresh and odor-free.


To effectively eliminate mildew smell after carpet cleaning, it is important to address the root causes of the odor. Moisture is a common culprit, so using a dehumidifier, keeping surfaces dry, and properly ventilating the room can help prevent mold and mildew growth.

Vinegar is a cost-efficient and effective way to deodorize and spot clean carpets. To use, combine one cup of distilled white vinegar with warm water in a spray bottle and spritz the entire carpet, allowing it to air dry.

It is important to note that if the odor persists, seeking professional carpet cleaning services may be necessary.