Is this mold in my crawlspace bad?

Moldy crawlspace

If you’ve spotted black mold in your crawlspace, especially in an older home without a vapor barrier, you’re not alone.

A homeowner recently asked, “Is this mold in my crawlspace bad?”

The short answer: While it’s probably not a five-alarm emergency, it’s a sign that your crawlspace needs attention.

If you’re concerned about crawlspace mold and want a free assessment for your home, please give us a call at (888) 586-3343 or send us a message. We’re here to help.

EDGE Energy stands out as a six-time ENERGY STAR Contractor of the Year. Since 2006, we’ve completed more than 5,000 projects in Maryland, Washington D.C., and Virginia,

What causes crawlspace mold?

Mold thrives in moist, poorly ventilated spaces – and crawlspaces are prime real estate if they’re not properly sealed. No vapor barrier? Poor insulation? Moisture can build up quickly, creating a breeding ground for mold.

Here’s what we typically recommend:

  • Install a reinforced vapor barrier to keep moisture from seeping up through the ground
  • Seal the crawlspace using closed-cell spray foam insulation on the walls and rim joists
  • Ensure the space is properly ventilated or conditioned to prevent future moisture issues

These upgrades help cut off mold’s moisture supply and keep your crawlspace clean and dry. Notice how the crawlspace pictured above is missing a vapor barrier, which means moisture from the ground can easily enter.

Crawlspace with no vapor barrier

When it might be more serious

If the mold is heavy, has a strong musty smell, or if someone in your home is sensitive to mold, you may want to look into professional mold remediation. But in most cases, proper encapsulation will dry things out and help the existing mold go dormant.

Bottom line: don’t ignore it

Mold in your crawlspace isn’t the end of the world, but it can get worse over time. And because your crawlspace air can make its way into your home, it could affect your indoor air quality and your family’s health.

The good news? A properly sealed and insulated crawlspace doesn’t just stop mold – it also helps cut your energy bills.

EDGE Energy offers free crawlspace and basement assessments. Since 2006, we’ve helped more than 5,000 homeowners in in Maryland, Washington D.C., and Virginia.


Call us at (888) 586-3343 or send us a message to schedule:

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