How to Dehumidify Your Car

  1. Research Center
    2. /
  2. How To Research Articles
    3. /
  3. How to Dehumidify your Car

Keep It Dry

Cars can collect moisture inside the cabin or trunk in any number of ways. Perhaps you left a window cracked during a rainstorm or have an older vehicle that doesn't seal as well as today's cars. Maybe you left wet camping gear in your SUV or a damp bathing suit and towels in your trunk. You definitely want to keep your vehicle dry on the inside to avoid trouble down the road. A wet or humid car can lead to mold or mildew forming and make the cabin smell awful! Plus, a car that stays wet inside can cause electronics to corrode and short out. You don't want that! 

Maybe you just live in a part of the country where wetness is an ongoing problem. I lived in Seattle for a number of years, where wet carpet can lead to real problems. No matter how your car got moisture inside it, we're going to show you how to dry it out and keep it that way. 
  • If your vehicle has wet flooring, first pull out the wet floor mats, dry them with a towel or hang them up somewhere to dry. Then use a wet/dry vac to remove any excess water from the floor of your car. If you don't own a wet/dry vac, you can rent one from most appliance centers or hardware stores. Remove the dry filter and suck out all the moisture you can. 
  • If you left the windows open during a major rainstorm, open the doors, dry up the water on the seats, door panels and dash with towels. After using the wet/dry vac, set up fans to dry the car out. Run the fans overnight if need be. Once the vehicle is fairly dry, use baking soda to absorb any remaining moisture. 
  • If you act right away to dry out the car, mildew should not form. Baking soda can be used on many different interior materials, including leather. Just Sprinkle baking soda on the floor and seats and let it remain for 24 hours before vacuuming it all up. 
  • If possible, do all of the above with the car outside in a sunny, dry area. The sun will help dry everything and reduce the risk of mildew or mold growing. 

How to Remove Mildew

If you purchase an older car that has mildew or mold growing in it, or if prolonged wetness causes these conditions, use the following steps to clean and remove the mildew. 

  1. First locate all the areas of the vehicle that have been infested with mildew, known for its musty smell. 
  2. Park in a dry, sunny spot to allow the sunshine to dry any dampness. 
  3. Remove and dry out your floormats in the sun. Locate all the areas where mildew or mold might be growing and scrub off the mold using a nylon brush. 
  4. Be sure to wear a face mask and latex gloves to protect yourself from mold. 
Do not use soap and water on the mold, just use the dry brush to scrub the mold to remove it from all car surfaces. If you are cleaning leather surfaces, use a soft brush to avoid scratching the leather. Vacuum up all the mold particles, then, while still wearing the mask and gloves, use vinegar or other mold deterrents such as Clorox, Biocide, or Concrobium to scrub the car clean. 

White distilled vinegar works great to remove mold from seats and carpeting. Let it sit and soak in for at least ten minutes. You might want to spot-test a small area of the interior with any mold cleaner you use to make sure it doesn't bleach or fade the material. 
Let the cleaner dry and then vacuum the entire interior of the car with a wet/dry vac. After cleaning the car completely, wash your hands thoroughly and change your clothing. Be sure to wash the clothes you wore while cleaning the mold out. You can follow up by spraying an anti-mold solution such as Mold Armor. 

Anti-Mold Powder can also be sprinkled on the seats, carpet, and floor mats to kill off any mold spores that you may have missed. Baking soda is an excellent mold preventative. Let it sit for twelve hours before vacuuming it up.

Keeping Mold Away

Sometimes water can enter a vehicle through a leaky sunroof, windows, or door panels that are not properly sealed. Place a container of Baking Soda or Damp Rid inside the car wherever moisture might be present. It will absorb the moisture for up to 60 days. 

Always remove wet clothing or other items right away and dry any damp areas as soon as you can. It is best to clean and vacuum the interior of your car every two weeks to keep it smelling fresh and clean. 

Best Dehumidifiers

Do you ever get in your car in the morning and notice condensation moisture on the inside of your windshield? Then you need a dehumidifier to reduce the chance of mold or mildew growing inside the vehicle. Using a dehumidifier also reduces allergens. 

Silica gel bags reduce humidity and moisture in your car and you can refresh them by placing them in the sun or popping them in the microwave. Many people place a silica bag on the dash, another on the floor in the back seat, and a third in the trunk. They are reasonably priced at under $15. Griot's Garage makes a great moisture dryer for your car. 
Electric dehumidifiers such as those produced by Vivosun can extract up to 250 milliliters of water per day in areas where humidity is over 90 percent. You'll find it on Amazon for $37.99. Eva-Dry makes an excellent cordless electric dehumidifier that is perfect for cars or boats and retails for $34.95. Â