Garage Smells Musty After Rain? Here’s How to Fix It!

Have you ever noticed a smelly musty odor in your garage after it rains? This is a common issue that many homeowners face due to high humidity levels. Garages can become damp and humid environments, especially during the rainy season, leading to unpleasant odors and potential health risks. In some cases, the smell may even resemble sewer gas.

A smelly garage with a musty odor may seem like a minor inconvenience, but it could be a sign of more significant problems such as mold growth or water damage. These issues can lead to respiratory problems, allergies, and other health concerns if left untreated. A musty house can also indicate these issues.

From identifying the source of the musty odor problem to implementing preventative measures, we’ll cover everything you need to know to keep your musty house smelling fresh and clean. Don’t forget to check your trash cans and garbage can as they can also contribute to the unpleasant odor.

So if you’re tired of dealing with a musty room or stinky garages smell after every rainfall, read on for some helpful tips and tricks on how to get rid of the unpleasant odor. One solution is to place a garbage can in the room or garage to reduce the smell.

Causes of Musty Smell in the Garage After Rain

If you notice a musty smell in your garage after rain, it could be a sign of moisture and humidity buildup. Here are some common causes of musty smells in garages after rain: garbage can, house, plants. To get rid of the smell, make sure to remove any wet items such as the garbage can or plants from the garage.

Presence of Moisture and Humidity in the Garage

Moisture and humidity can easily accumulate in garages, especially during rainy seasons. In case there is too much moisture, it can cause dampness, which leads to mold and mildew growth. Mold and mildew produce an unpleasant odor that can linger for days or weeks, resulting in a musty house. To get rid of this problem, consider adding plants in your garage. Plants can help absorb excess moisture and improve air quality.

To prevent the buildup of musty odors in your garage, ensure that there are no leaks or water seepage from walls or roof. You should also avoid storing wet items such as mops, towels, and gardening tools inside the garage. In case you have plants in the garage, make sure to water them outside the house to avoid excess moisture.

Poor Ventilation Leading to Stagnant Air

Garages, in most cases, often have poor ventilation since they are not designed for living spaces like a house. Without proper air circulation, the air inside the garage becomes stagnant and stale. This can lead to bad odors caused by mold growth, which is a common case.

To improve ventilation in your garage and prevent a musty odor from spreading to your house, consider installing vents or fans that allow fresh air to circulate freely. You can also open windows and doors when possible to let fresh air into the space.

Water Seepage Through Walls or Roof

Water seepage through walls or roof is a common cause of musty smells in garages and houses after rain. If water enters through cracks or gaps on the walls or roof, it can create a damp environment that promotes mold growth.

To prevent water seepage through walls or roof in your house, inspect your garage regularly for any signs of damage such as cracks, holes, or gaps. Repair any damages immediately to prevent further water infiltration that can cause a musty odor.

Mold and Mildew Growth Due to Dampness

Mold and mildew thrive in moist environments with poor ventilation. When there is too much moisture in the house garage, it creates a conducive environment for mold and mildew growth. These fungi produce a musty odor that can be quite unpleasant.

To prevent mold and mildew growth in your garage, ensure that the space is dry at all times to avoid musty odor lingering in your house. You can use a dehumidifier to reduce moisture levels or open windows and doors to let fresh air circulate.

Addressing Moisture Buildup in the Garage

Installing a Dehumidifier to Reduce Humidity Levels

One of the most effective ways to address moisture buildup in your house garage is by installing a dehumidifier. A dehumidifier works by removing excess moisture from the air, making it an ideal solution for garages that smell musty after rain.

When choosing a dehumidifier, consider the size of your garage space and the amount of moisture and musty odor present. There are different types of dehumidifiers available on the market, including portable and whole-house options.

Portable dehumidifiers are ideal for smaller garages and can be moved around as needed. Whole-house dehumidifiers are designed to cover larger areas and are typically installed directly into your home’s HVAC system.

Improving Ventilation by Opening Windows or Installing Exhaust Fans

Another way to reduce moisture buildup in your house garage is by improving ventilation. This can be done by opening windows or installing exhaust fans.

Opening windows in your house garage allows fresh air to circulate throughout, which helps to reduce humidity levels. If you don’t have windows in your house garage, consider installing exhaust fans instead. Exhaust fans work by pulling moist air out of your house garage and pushing it outside.

Sealing Any Gaps or Cracks That Allow Water Seepage

Gaps or cracks in walls and floors of your house can allow water seepage into your garage, leading to mildew growth and mold growth. To prevent this from happening, make sure to seal any gaps or cracks that you find.

For small gaps or cracks in your house or garage space, use caulk to fill them in. For larger gaps or cracks in your garage floor or around garage doors, use foam insulation spray or hydraulic cement.

It’s also important to check your house’s garage doors for any gaps that may allow water seepage. If you notice any gaps around your house’s garage door, use weather stripping or a door sweep to seal them up.

Using Waterproof Coatings on Walls and Floors

Another way to prevent moisture buildup in your house garage is by using waterproof coatings on walls and floors. There are different types of waterproof coatings available, including epoxy and concrete sealers.

Epoxy coatings are ideal for garage floors in a house as they provide a durable, non-slip surface that is resistant to motor oil and mineral oil spills. Concrete sealers are designed to penetrate deep into the concrete of a house, creating a barrier against water seepage.

Cleaning Floor Drains and Sinks to Eliminate Musty Odors

Removing debris and dirt from drains using a plumber’s snake or brush

One of the main reasons for musty odors in garages and houses after rain is the accumulation of debris and dirt in floor drains. Over time, this debris can accumulate and cause blockages that prevent water from draining properly, leading to stagnant water that emits an unpleasant odor. To eliminate this problem, it’s important to remove any accumulated debris and dirt from the drain.

A plumber’s snake or brush is an effective tool for removing debris from floor drains in a stinky garage. The snake is inserted into the drain until it reaches the blockage, where it can be used to break up any clogs or obstructions. A brush can also be used to scrub away any buildup on the walls of the drain, especially in garages with limited garage space and garage doors.

Flushing drains with hot water, vinegar, or baking soda solution

Once you’ve removed any visible debris from your stinky garage floor drain, you should flush it out with hot water to clear away any remaining residue. Hot water helps dissolve grease and other substances that may have accumulated in your drain over time. Make sure to keep your garage doors open during the process for proper ventilation.

Another option is to use a mixture of vinegar and baking soda. This solution can also be used to clean your garage floor and garage doors. Pour a cup of baking soda down the drain followed by a cup of white vinegar. Wait for 10-15 minutes before flushing with hot water.

Chlorine bleach can also be used as an alternative method for cleaning floor drains but should be used sparingly due to its harshness on pipes.

Checking for leaks under sinks and repairing them promptly

Another common source of musty odors in garages after rain is leaking pipes under sinks. When pipes leak, they create damp conditions that are ideal for mold spores and fungus growth, which leads to musty smells.

To prevent this problem, regularly check under sinks for signs of leaks such as puddles or wet spots around pipes. If you find evidence of a leak, repair it promptly to prevent further damage.

Checking air ducts and HVAC systems

If the musty odor persists even after cleaning floor drains and sinks, it may be time to check your garage’s air ducts and HVAC system. Over time, these systems can accumulate dust, mold spores or fungus that can lead to unpleasant smells.

A professional HVAC technician can inspect your system for any signs of mold growth or debris buildup. They can also clean the system thoroughly, which will improve its efficiency and reduce energy bills.

Getting Rid of Dirty Garbage and Recycling Bins

Regularly Cleaning Garbage Cans with Soap and Water

One of the main reasons that your garage may smell musty after rain is due to dirty garbage cans. Over time, garbage cans can accumulate debris and dirt, leading to a build-up of bacteria that can cause unpleasant odours. To prevent this from happening, it’s important to regularly clean your garbage cans with soap and water.

To clean your garbage cans, simply follow these steps:

  1. Empty the contents of the bin into a trash bag or recycling bin.
  2. Rinse out the inside of the bin with clean water.
  3. Add some dish soap to a bucket of warm water.
  4. Use a scrub brush or sponge to scrub down the inside and outside of the bin.
  5. Rinse out the bin thoroughly with clean water.
  6. Allow the bin to air dry completely before using it again.

By cleaning your garbage cans regularly, you’ll be able to remove any built-up debris or dirt that could be causing unpleasant odours in your garage.

Disinfecting Bins with Bleach Solution

In addition to cleaning your garbage cans regularly, it’s also important to disinfect them every once in a while. Disinfecting your bins will help kill any bacteria or germs that may have accumulated over time, preventing bad smells from developing.

To disinfect your bins, you can use a bleach solution:

  1. Mix ½ cup bleach with 1 gallon of water in a bucket.
  2. Pour the solution into each bin until it covers all surfaces inside.
  3. Let sit for 10-15 minutes before rinsing out thoroughly with clean water.
  4. Allow bins to air dry completely before using them again.

It’s important not to mix bleach with other cleaners as this can create harmful fumes.

Keeping Bins Dry by Placing a Lid on Them

Another way to prevent bad smells in your garage is by keeping your bins dry. If water gets into your garbage cans or recycling bin, it can cause bacteria and germs to grow, leading to unpleasant odours.

To keep your bins dry, make sure to place lids on them after use. This will help prevent rainwater from getting inside and causing problems.

Other Tips for Keeping Your Garage Smelling Fresh

In addition to cleaning and disinfecting your garbage cans and recycling bin, there are other steps you can take to keep your garage smelling fresh:

  • Clean up any spills or messes promptly.
  • Use a litter box with a lid for pets.
  • Avoid storing dirty laundry or kitty litter in the garage.
  • Break down cardboard boxes before placing them in the recycling bin.
  • Store items in sealed containers instead of leaving them out in the open.

By following these tips, you can help prevent bad smells from developing in your garage after rain.

Dealing with Urine and Sewage Smells After Rain

Dealing with a musty smell in your garage after rain can be frustrating. The smell can be caused by various factors, but one of the most common is sewage smells. Sewage smells are not only unpleasant but also pose health risks to you and your family.

Identifying Sources of Sewage Smells

The first step in dealing with urine and sewage smells after rain is identifying the source of the problem. Some common sources of sewage smells include:

  • Broken pipes
  • Clogged sewer lines
  • Leaks in plumbing systems
  • Standing water in drains or basements
  • High humidity levels

If you notice a persistent smell that doesn’t go away even after cleaning your garage thoroughly, then it’s likely that you have a sewage issue.

Hiring Professionals to Fix Plumbing Issues Causing Sewage Smells

Fixing plumbing issues causing sewage smells can be challenging, especially if you don’t have any experience in plumbing. That’s why it’s essential to hire professionals who specialize in fixing such issues.

When hiring a professional plumber, ensure they are licensed and experienced. A licensed plumber has undergone training and knows how to deal with different plumbing problems effectively.

Cleaning Affected Areas Thoroughly Using Disinfectants

After fixing the underlying plumbing issue causing the smell, it’s time to clean up any affected areas thoroughly using disinfectants. Here are some tips for cleaning affected areas:

  • Wear protective gloves when cleaning.
  • Use hot water and soap to clean surfaces.
  • Disinfect surfaces using bleach or other disinfectants.
  • Ventilate the area by opening windows or using fans.

It’s important to note that if there is standing water in your garage due to heavy rains, it should be removed as soon as possible as standing water can lead to mold and bacteria growth.

Preventing Future Sewage Smells

Preventing future sewage smells is crucial to ensure that the problem doesn’t reoccur. Here are some tips for preventing future sewage smells:

  • Regularly inspect your plumbing system for leaks or clogs.
  • Ensure that all drains have traps installed to prevent sewer gas from entering your home.
  • Keep your garage well ventilated by opening windows or using fans.
  • Address any moisture issues in your garage, such as leaks or high humidity levels.

Effective Solutions to Get Rid of Musty Smell in the Garage

Using Odor Absorbers

One of the most effective ways to get rid of musty smells in the garage is by using odor absorbers like activated charcoal or baking soda. These substances work by absorbing moisture and neutralizing odors, leaving your garage smelling fresh and clean.

  • Activated charcoal: This is a highly porous form of carbon that is great for absorbing odors. Simply place a few bowls of activated charcoal around your garage, and let them sit for a few days. Afterward, remove the bowls and dispose of the used charcoal.
  • Baking soda: Another excellent odor absorber is baking soda. Sprinkle it on your garage floor, leave it overnight, then sweep it up in the morning. You can also place an open box of baking soda in your garage to absorb any lingering odors.

Applying Natural Remedies

If you prefer natural remedies over chemical solutions, there are several options available to help get rid of musty smells in your garage.

  • Essential oils: Certain essential oils like tea tree oil, peppermint oil, and eucalyptus oil have antimicrobial properties that can help eliminate musty odors. Mix a few drops with water in a spray bottle and apply it around your garage.
  • Citrus peels: The natural oils found in citrus peels can also be used to combat musty smells. Place orange or lemon peels around your garage or boil them in water on the stove for an hour to release their scent.
  • Coffee grounds: Used coffee grounds are another natural remedy that can help absorb unwanted odors. Spread them out on a tray and leave them in your garage for a few days before disposing of them.

Using Commercial Odor Eliminators

If you prefer commercial products over DIY solutions, there are many odor eliminators specifically designed for garages that you can use.

  • Vinegar: This common household item is a great natural odor eliminator. Mix equal parts water and vinegar in a spray bottle and apply it around your garage. You can also leave bowls of vinegar around your garage to absorb odors.
  • Methane gas: This may sound strange, but methane gas is actually an effective odor eliminator. You can purchase small packets of methane gas online or at your local hardware store and place them around your garage to eliminate musty smells.

Tips on Preventing Musty Smell from Returning in the Future

In conclusion, preventing a musty smell from returning to your garage after rain is crucial for maintaining a fresh and clean environment. Addressing moisture buildup, cleaning floor drains and sinks, getting rid of dirty garbage and recycling bins, dealing with urine and sewage smells, and using effective solutions are all essential steps to take.

To prevent future musty smells, ensure proper ventilation in your garage by opening doors or windows. Consider investing in a dehumidifier to reduce humidity levels. Regularly inspect and fix any leaks or water damage in the garage. Keep the area clean and clutter-free to avoid moisture buildup.

Remember that prevention is key. By taking proactive measures, you can keep your space smelling fresh and clean.


Q: Can I use air fresheners to get rid of the musty smell?

A: While air fresheners may temporarily mask the odor, they do not address the root cause of the problem – moisture buildup. It’s best to focus on addressing the source of the issue rather than relying on quick fixes like air fresheners.

Q: How often should I clean my garbage and recycling bins?

A: It’s recommended that you clean your garbage and recycling bins at least once a month to prevent them from becoming breeding grounds for bacteria and mold.

Q: What if I have tried all these solutions but still have a musty smell?

A: If you have tried all these solutions but still have a persistent musty smell in your garage after rain, it may be time to call in professionals such as mold remediation specialists or plumbers who can assess potential hidden sources of moisture or damage.

Q: Can I use bleach to clean my floor drains?

A: Yes, bleach can be an effective solution for cleaning floor drains. Mix one part bleach with ten parts water and pour it down the drain. Let it sit for 10-15 minutes before flushing the drain with hot water.

Q: How long does it take for a dehumidifier to reduce humidity levels in my garage?

A: The time it takes for a dehumidifier to reduce humidity levels depends on various factors such as the size of your garage, the level of humidity, and the capacity of your dehumidifier. Generally, it can take anywhere from a few hours to several days to see significant results.