Required Roof Conditions for Infrared Flat Roof Moisture Survey
The requirements listed below are based on current industry standards, including those published by ASTM, RCI and Infraspection Institute. Compromising on any of these requirements may adversely affect the results of the Infrared Flat Roof Moisture Survey.
Dry Roof Membrane: The roof membrane must be dry at Sunrise. Areas that had moisture at Sunrise may not have enough solar loading to show the necessary thermal patterns. Since an infrared imager cannot “see through water”, any areas with the presence of ice, snow, or standing water cannot be surveyed.
Solar Loading: The day of the Survey should be a mostly sunny day, providing good solar loading. A general rule of thumb is if the roof surface or a nearby similar surface (i.e. parking lot, street or sidewalk) is warm to the touch, the roof will be warm.
Minimum Daytime Temperature: Daytime high temperatures should be at least 40° F. If temperatures do not rise above this point, wet areas of the roof are likely to remain frozen and not absorb solar energy. Without solar loading, thermal images indicative of moisture are not likely to be identified.
Winds of less than 15 mph: During daytime hours and at the time of the Survey, winds should be less than 15 mph. In addition to being a safety issue when on the roof, stronger winds can result in a cooling effect that may cause thermal images not to be seen.
No precipitation on the day of the Survey: Moisture that falls during the day of the Survey will interrupt normal solar loading and cooling of the roof surface. Even if evaporation results in the roof surface drying, the effects of the evaporation can interfere with the thermal images.