Case Study: Water spill and hidden moisture created 9,700 Chaetomium spores

A homeowner noticed brown growth around the floorboards in their home office. A water purifier had overflowed weeks earlier, and although the spill was cleaned up, moisture remained trapped beneath the vinyl hardwood flooring where a gap at the wall allowed water to seep underneath. Combined with heavy rainfall and existing basement humidity issues, the conditions created an environment for mold to flourish.

The homeowner's spouse was especially concerned about mold exposure in their home. Claro performed a comprehensive assessment that revealed the office issue was just the beginning. The basement had its own contamination, including the presence of black mold, confirming that a multi-phase approach would be needed.

Pre-treatment testing after demolition revealed severe contamination in two areas. The home office registered 15,000 spores per cubic meter, dominated by Chaetomium at 9,700 spores, a definitive water-damage indicator confirming prolonged moisture exposure beneath the flooring. Penicillium/Aspergillus measured 3,200 spores and Basidiospores at 2,200.

The basement was also contaminated: 4,900 total spores including Chaetomium at 1,200, Penicillium/Aspergillus at 1,300, and Stachybotrys (black mold) at 67 spores. Hyphal fragments measured 210, indicating active mold growth nearby. What started as a simple water spill in one room had spread through the home, with the basement showing signs of its own moisture-driven contamination from years of inadequate humidity control.

The project required multiple phases. First, Claro - Complete Mold Remediation set up containment and performed demolition: removing vinyl hardwood flooring and drywall in the office to expose the water damage source near the patio door, and removing all carpet and ceiling tiles in the basement. Antimicrobial wipe-down was performed on identified surfaces. A professional-grade Aprilaire dehumidifier was installed with dedicated electrical to permanently manage basement humidity.

A second phase addressed additional leak-related demolition work, affected ceiling tile removal, and basement dehumidification. Once all affected areas had dried sufficiently and moisture levels were verified, Claro performed the whole-home and HVAC dry fog treatment using InstaPure and EverPure across the entire 2,445 square foot home.

Post-treatment testing confirmed dramatic results. The home office dropped from 15,000 spores to just 53 CFU/m3, with the catastrophic 9,700 Chaetomium completely eliminated. The basement dropped from 4,900 spores to less than 13 CFU/m3, with both the Stachybotrys and Chaetomium gone entirely. The homeowners had lab-verified proof their home was clean, backed by Claro's one-year guarantee.