Fungal conditions and resultant damages within structures have become a major concern and liability for both private and public sectors. Increased attention to these issues have been fueled by litigations, fungal-related property claims, health-related publicity campaigns and perceived or actual liability in real estate transactions.

Fungal investigators such as Certified Indoor Environmentalist, engineers, scientists and building/mechanical specialists, have identified many common causal conditions that result in fungal growth within structures. Appropriate handling of fungal damages requires a detailed and efficient approach to evaluate these potential causal conditions and to identify the origin and cause (O&C) of the fungal problem.

Determination of the O&C becomes a crucial step in the decision-making process for property owners, insurance companies and attorneys in assigning liability. Though not justified in all cases, an investment in a thorough O&C investigation can be money well spent in very large or complex situations that may result in claims or litigation. Accurate O&C investigations accomplish two goals, which are 1) making remediation more effective by preventing the source or conditions from reoccurring, and 2) assisting in limiting or assigning liability to the appropriate party(s).

The fungus occurs because of natural conditions and is an important process in the breakdown and natural recycling of organic materials. Problems begin when these conditions occur within an enclosed, or even occupied environment where an effect on building materials and an increased risk to human health may occur.

Three general components and conditions that are required for fungal growth in occupied structures are the following:

The presence of fungal spores in nature, a food source (cellulose) within building materials, and moisture intrusion due to systems failing in the building or structure.

Temperature can also be a factor, most fungi can flourish in temperatures provided by conditioned (properly or improperly) indoor environments, typically ranging from 60 to 90 degrees Fahrenheit.

The presence of moisture is the catalyst for the development of fungal conditions and is the primary focus of O&C investigations. Relative humidity, generally greater than 70%, can provide the moisture necessary to generate fungal growth. A moisture content of greater than 20% in common building materials can also be adequate to support the fungal growth.