Mold Problems Indoor mold problems have resulted in school closings and multi-million dollar renovations. School districts and administrators have to deal with the mold panic fueled by these closings and the media coverage. Mold contamination in schools is a serious problem that will affect sensitive teachers and children. Preventing mold problems does not require completely redesigned HVAC systems costing tremendous amounts to install and operate. There are affordable, practical solutions that will eliminate mold growth in schools and avoid the costly mold remediation and mitigation measures necessary after widespread contamination has occurred. For more information, see Mold In Schools. Mold Spores Only Need Food and Water to Grow Molds feed on organic materials. The drywall paper, books, wallpaper and paste, wood, paper, some paints and dirt are all a food source for mold. You cannot eliminate the food source for mold. Molds do not require liquid water to grow. They only require humidity levels from 65 to 99 percent at the surface on which they grow. If you control the humidity, you can eliminate mold growth. Building defects like roof leaks or ruptured pipes are commonly assumed to be the moisture source if mold problems are encountered in a school. The truth is that fresh air ventilation is the largest moisture source in a school. The volume of water brought into a building through ventilation is sufficient to sustain mold growth. This humidity also prevents the occasional wetting from roof leaks or other defects to properly dry. This leads to the mistaken belief that simply fixing the defects will fix the mold problem.