10 reasons there could be mold regrowth after an effective remediation

Recent article in the Journal of Cleaning, Restoration and Inspection, "Mold Regrowth After Effective Remediation" (Nolan B. Wells: R.E. Moon): "Months after a water-loss restoration, you get a call complaining of mold growth on contents. In the absence of a plumbing leak or exterior water infiltration, there are a number of reasons why surface mold can return months after a competent water-remediation effort."

1.     Fan in the “on” position—moisture from evaporator coils recycles portion of removed water vapor into supply air stream, and gets redistributed throughout the entire home.
 2.     Temperature across evaporator coils too low—when it fails to drop below dew point, moisture won’t condense and dehumidify the air.
 3.     Installation of larger/more efficient HVAC system—may short cycle and reduce dehumidification, increased moisture encourages surface microbial growth.
 4.     Thermostat-humidistat wiring (series or parallel)—differs in moisture management.
 5.     Negative pressure from mechanical exhausts—ventilation can introduce unconditioned air to interior surfaces, causing condensation/moisture.
 6.     Poor bathroom to HVAC circulation—non-ducted HVC ventilation results in diminished air circulation and gives opportunity for moisture to be absorbed into materials in the home.
 7.     Operational error—elevated humidity is a concern post-remediation.
 8.     Diminished sensible heat load—diminishes effectiveness of HVAC dehumidification.
 9.     Thermal gradients from opposing floor or ceiling—condensation can occur if the thermal gradient is too large.
 10.  Reintroduction of contaminated contents—bringing the previous issue back into the clean home.