How to Remove Bad Odors from a Crawl Space


Angela asked: How do I remove rotten food odors in the crawl space from a broken sink drain? The drain pipe under my house for the kitchen sink broke, and everything that was washed down the drain (garbage disposal waste, dirty rinse water, cleaning products). These are now piled up on the gravel in the crawl space of my home. I’m not sure how long it was like that, but I think the cold weather was covering up the smell. Now that it is warmer, the smell is sickening and unbearable. The crawl space is not easy to access. What can I put on the pile to dissolve it or get rid of the smell? I believe it has soaked into the ground underneath, so removing the food won’t remove the smell.

Once moisture penetrates a crawl space, mold, mildew, and their companionable odors are sure to follow. Unfortunately, there’s not a fast and easy solution to these odor problems. The most effective tactic is a good moisture barrier (also known as a vapor barrier), and for that you need to call in a professional. For a short term solution, you can give this a try.

You Will Need:

  • Industrial strength fan
  • Access to electricity
  • Outdoor extension cord (if needed)
  • Shovel
  • Dirt

Steps to Remove the Odor:

  1. Choose a dry sunny day without any chance of rain. Low humidity is a plus.
  2. Open all vents to the crawl space.
  3. Place the fan at the vent closest to the odor and turn it on high. It will pull air through the other vents, causing an increase in circulation that, with any luck, will dry the space.
  4. Allow it to run for at least 8-10 hours.
  5. If you can access the pile of food, the quickest way to remove the food and the odor is to bury it.
  6. If possible, cover the food with dirt. It will naturally decompose in the soil, and the dirt covering the top will help to block the odors.

Additional Tips and Advice

  • Do not attempt to do this when it’s raining. Likewise, make sure the fan and all electrical connections are clean and dry and the cord is in good repair.
  • In many cases, the added air circulation will serve to dry the crawl space, ridding it of the odor resulting from mold and/or mildew.
  • Another (likely more expensive) option is to use a dehumidifier. Consult with a professional at a home improvement store to determine the size and model that might be right for your job.
  • If you want the food to decompose faster, check into purchasing enzymes that are used in composters. These can be spread over the debris to help the decomposition along. The sooner the food is decomposed, the sooner your problems will be gone. The enzymes are available from many online stores.


  1. Randy says:

    Should I treat the affected dirt and what should I use?

  2. Marilyn says:

    I put lime on the area to help decompose the garbage. That was a week ago and the smell is still there. I think it will just take time for it to dissipate.

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