Infrared roof moisture surveys utilize a highly sensitive infrared camera to scan an entire roof for the purpose of locating areas of wet insulation. Infrared scans are typically conducted in the evening after the roof surface cools down.
The basic principle involved centers around the fact that areas of wet insulation absorb more solar radiation during daylight hours, as compared to areas of dry insulation.Consequently, as the roof surface cools down at night, these wet areas release comparatively higher amounts of stored heat. The infrared camera senses the corresponding temperature differentials and electronically displays them as a digital video image. These images can then be recorded and printed out as photos (thermograms) showing the outline and distribution of the wet areas. Typically, while the thermographer is scanning the roof, an assistant will mark the roof, painting and outlining all wet areas.
Core samples are taken to determine the exact composition of all materials and to verify the results of the scan. A written report and corresponding scaled roof plan are then provided, summarizing all findings and showing the locations and amounts of wet insulation.