Mold – Crawl Space: Procedure for Cleaning

Cause: The primary cause of crawl space mold is water leaks, especially hot water lines.

Insurance: Limits for mold in crawl spaces due to water leaks may be capped at $5k. Proceed accordingly.

IICRC: Presently the IICRC standard specifies abrasive means to remove mold. We do not follow this outdated method. It costs easily 2x, and up to 5x more than our modern method.

Visqueen: Use judgement on need for removal and replacement.

Chemistry:

  • Chem Decon A/B for fogging

    • Recommend multiple cases

  • MSR+ for surface spray of sheathing

    • Recommended multiple cases

    • Note: Do not wear PuroClean hoodie near MSR+

Equipment:

  • PPE – Yellow coveralls, Full Face Respirator, gloves

    • OK to wear White PPE under Yellow.

  • Headlamp or crawlspace lighting

  • Knee Pads recommended

  • Multi-Sprayer® sprayer

    • Must be flushed out on-site or immediately upon return to shop

  • ULV fogger, Airofog

    • Must be flushed out on-site or immediately upon return to shop

Step-by-Step Instructions

Step 1: Preparation

  • Inspect crawl space for visible mold on joists, subfloor, insulation, and visqueen. Take photos. Record relative humidity (RH). Recommend drying if RH > 60%.

  • Inspect insulation. If wet, remove and replace after treatment is complete.

  • If insulation is visibly mold-contaminated, remove and bag for disposal. If not, leave in place and treat exposed surface.

Step 2: Safety and Containment

  • Wear full PPE.

Step 3: Surface Cleaning – Remove Mold Stains

  • Spray Artemis MSR+ directly onto visible mold on flooring and joists. Wipe off with cotton rags if necessary. Take great care to not spray MSR+ on anyone or yourself.

Step 4: Volume Fogging – Spore Knockdown, Insulation Treatment, Flooring Sealing

  • Fog entire attic space with Artemis Chem Decon A & B using ULV fogger. Reach all sheathing, joists, insulation, and air volume.

Step 5: Dry Out (if necessary)

  • Set dehumidification and air as appropriate.

Step 6: Reinstall Treated Insulation

  • If insulation was kept and treated, reinstall it after fogging. If replaced, install new insulation after full drying.

Step 7: Documentation

  • Record photos, chemical volumes used, insulation removed, and any follow-up recommendations.

By following this procedure, crawl space mold can be safely and thoroughly treated under confined conditions, reducing health risks and helping to prevent future growth through moisture control.