Infrared & Nuclear Roof Moisture Surveys

Save Costs with Moisture Surveys

Water infiltration is one of the roofing industry’s most costly problems. Roof leaks can lead to a breakdown of insulation, loss of insulating properties, structural deck deterioration and property damage; all of which cost building owners billions of dollars every year. This often results in complete removal and replacement of all roofing materials; in many situations these replacements may have been premature to the potential service lives of the installed roofing systems.

Moisture surveys can determine if, where, and to what extent detrimental moisture has compromised a roofing system. By making this determination, a building owner may have more options with regard to corrective actions. A moisture survey can save an owner significant costs by allowing him to replace only the damaged areas of roofing rather than the entire system. Moisture surveys can also be a valuable tool to verify if a new roof installation has been installed and completed without moisture compromise.

Here at RCS, we utilize two types of non-destructive moisture surveying: infrared and nuclear.

Infrared Survey

RCS utilizes Flir thermal imaging cameras to perform infrared roof moisture surveys. With these thermal imaging cameras, we are able to see where moisture is trapped within the roof system. The survey is performed after sundown in order to allow thermal differences or “anomalies” to occur once the air and roof surface temperatures reach a state of equilibrium.

During the day, moisture within the roof insulation is heated and then it retains that heat into the night longer than the dry insulation. This results in thermal anomalies (areas that are warmer) that can be detected by our infrared cameras. These anomalies are then considered as suspect wet areas and are outlined on the roof surface with spray paint. Roof cores are taken in both dry and suspect wet areas to verify the instrument readings. Finally, the locations of the anomalies and the test cuts are marked on a roof plan.

Nuclear Survey

A nuclear moisture survey provides accurate mapping of moisture concentrations (by density) within a roofing assembly. RCS utilizes Troxler roof moisture gauges for the nuclear surveys. We begin by marking the intersecting points of a 5′ x 5′ grid pattern on the entire roof surface with paint or chalk. A reading is then taken at each grid point with the nuclear gauge and it is recorded on a roof plan marked with the same grid. Once all the readings have been recorded, the technician then takes a roof core in the area with the highest numeric reading to determine if moisture is present. If moisture is found, then additional roof cores are taken at lower readings until dry roofing is found. Finally, a histogram (or bar graph) of all the numerical readouts is developed. This histogram enables RCS to determine what percentage of the roof area is affected by moisture intrusion.

Don’t let the word ‘nuclear’ scare you. These gauges are all fully contained and all of our personnel that use them are thoroughly trained in their use and transport. RCS is properly licensed by the Nuclear Regulatory Commission for transport and use of the devices and we perform regular leak testing as required by our licensing.