Moisture Detection

A key to prevention of mold growth.

Mold has existed in our environment long before the recent awareness of its presence in homes and businesses. The impact of mold on health is dependent upon the concentration of spores in the immediate area and the allergic effect on an individual. Potential health problems associated with mold exposure can take the form of allergic reactions or asthma. The problem is not limited to homes. Commercial buildings with moisture accumulation due to condensation or leaks are a candidate for mold growth. The mold topic has reached such proportions that congress has introduced a bill titled “United States Toxic Mold Safety and Protection Act of 2002” also know as the “Melina bill”.

According to the U.S. Environmental Protection Agency, there is no practical way to eliminate mold spores in an indoor environment. The best way to control mold growth is to control moisture. Mold can begin growth in as little as 24 hours. Roof leaks and water pipe leaks are common sources of water accumulation that may cause mold growth. Mold has closed public schools and caused companies to spend millions of dollars on environmental tests and remediation. Clearly, there is more reason to become aware of roof conditions, before water begins dripping on a building owner’s head.

Moisture present in roofs and walls can be detected with a sensitive infrared camera, under the right conditions. Infrared roof inspections are performed most effectively after sunset, when the roof gives off its heat energy accumulated during the day. The heat capacity of moisture soaked roof insulation is greater than that of dry insulation. As a result, the moisture soaked roof areas appear quite clearly when performing an infrared scan.

Similarly, it is possible to detect moisture located behind interior walls with an infrared camera, under the right conditions. The temperature difference created by the presence of moisture on the inside surface of a wall will appear differently than the surrounding area.

Infrared inspection is a fast, non-invasive method to discover moisture intrusion within the building envelope. Infrared inspection does not directly detect the presence of mold, rather it may be used to find moisture where mold may develop. The limitations to obtaining accurate infrared images pertain to the ability of the surface being scanned to emit heat energy. Gypsum (dry wall) in interior walls emits quite well, whereas highly reflective surfaces do not. Since the temperature difference between the wet and the dry wall are very slight, a sensitive infrared camera must be used.

Further information regarding mold may be found on the following sites:

http://www.epa.gov/iaq/molds/moldresources.html
http://www.cdc.gov/nceh/airpollution/mold/
http://www.ci.nyc.ny.us/html/doh/html/epi/epimold.html