The Example plant roof was the subject of an aerial infrared roof moisture survey on the evening of March 15, 1998. The weather was warm and dry with few clouds in the vicinity and light westerly winds, providing good infrared imaging conditions. The roof was photographed earlier that same day.

		Aerial Infrared Thermography Infrared Thermograms are taken of the building.
		Aerial Photography Visual Photos are taken of the building.
		AUTO CAD Drawings Fully Scaled Auto CAD Drawings are created

This report consists of:

Note: Example plant provided AutoCAD drawings of the plant roof that are the basis for the drawings included with this report package. Roof top equipment is drawn in a brown color, while suspected wet areas are in red and blue. The drawings are more than adequate for the purpose of locating and marking suspected roof system damage.

Definitions

Probable Wet Area - An area of the roof system shown as a 'hatched' area on the roof drawing that is highly suspected of containing entrained moisture in the underlying roof insulation.

Possible Wet Area - An area of the roof system shown as a 'dashed' area that is suspected of containing entrained moisture, but whose thermal signature is weaker than a 'probable' wet area and may be the result of factors other than entrained moisture that are causing the retention and transmission of heat. Such signatures may be the result of excess ballast material, roof patches, dark stains and the like, or, they may be areas of wet roofing but are less saturated than areas labeled as 'probable'.

Analysis

The Example plant roof area is approximately 1,816,230 square feet (SF), which includes a newer roof section in the northeast quadrant of the building and a separate small building on the south end of the plant. There are 96 areas of 'probable' wet insulation noted within the building's roofs amounting to 311,793 SF (17.2% of the roof area). Several of the factory's 'small' peripheral roofs are believed to mostly or completely saturated with water contamination (front entrance roofs and roofs on the south end of the plant). In addition, the large, heavily damaged roof area toward the north end of the plant comprises nearly two-thirds of the 'probable' wet area noted (198,367 SF out of a total 311,793 SF). We understand this entire area is, or soon will be, under repair/replacement. If so, and this large area is eliminated from the calculations, then we suspect 113,426 SF of probable wet area (6.2% of the total roof area). There are also 30 'possible' wet areas totaling 11,020 SF (0.6%). The suspected 'possible' and 'probable' wet areas are located throughout the roof system, although the majority of the remaining 'probable' wet area is confined to a single roof area in the southeast quadrant of the plant. On many of the 'possible' wet areas there are corresponding dark stains and/or dirt accumulations on the roof which are known to cause false indications of wet areas-these type areas are classified as 'possible' until confirmed wet. Please refer to the accompanying drawings for a visual representation of the foregoing information.

Infrared thermograms are included as a guide to the anomalies and the roof areas in which they are found.

Recommendations

We recommend the Example roof maintenance team review the videotape provided which will have the highest resolution and contrasting infrared images of the roof areas. Then, with the aid of the AutoCAD drawings and thermograms, physically locate the anomalies noted as 'probable' wet areas on the roof and conduct a destructive test (core sample) within those areas. The 'possible' wet areas should be examined to see if there is some indication why they would retain more heat than the rest of the roof-such as a build-up of dirt or other heat absorbing contaminant on the roof. If necessary, destructive tests should also be accomplished within these areas to determine if they contain wet insulation. When test results are noted, a maintenance decision can be made concerning repairs. If the results are provided to us, we will update the drawing and forward a copy of the file to the company. Within six months to one year, Example Maintenance management may wish to conduct another roof moisture survey to confirm interim repairs and to find additional/new areas of damaged roofing. Usually, after two to three cycles of infrared roof moisture surveys and repairs, roof owners and maintainers find that the cost of maintaining the roof system decreases dramatically and the service life of the roof is extended, resulting is substantial savings.