Case Study 09036: Successful Attic Mold Remediation

Facts/History/Observations:

An initial inspection by GML revealed that the mold Cladosporium was actively growing on plywood roof sheathing and on both gable ends in the attic.  A professional mold remediation company was hired to clean all surfaces in attic under environmental controls and using standard mold remediation procedures.  After the work was completed, we re-inspected the attic to determine if remediation was successful.

Attic insulation was removed, leaving the topside of the second floor ceiling Sheetrock exposed. Among several other important steps, the plywood sheathing was dry-ice blasted (similar to sand blasting except dry ice pellets were used as the abrasive agent).  Visual evidence of mold was no longer present.

Inspection Strategy:

• Visual inspection of attic
• Surface swab sampling from several representative areas of the previously moldy plywood sheathing

Lab Results:

• Lab results describe a negligible amount of mold spores
• The current level of mold on wood materials in the attic is normal
• Remediation was completely successful

Recommendations:

• Maintain a dry and well ventilated attic
• Re-install insulation