During the day, the sun radiates solar energy onto the roof and into the roof substrate. Then at night, the roof radiates this heat back into outer space. This is called “radiational cooling” as the heat from the roof is radiated into the cooler upper atmosphere. Areas of the roof that are of a higher mass (wet) retain this heat longer than that of the lower mass (dry) areas. Infrared imagers can detect this subtle heat difference and “see” the warmer, higher mass areas, during the “window” of uneven heat dissipation.
Infrared thermography views objects such as roofs in the two different wavelength (short wave, at 3000 to 5000 nanometers and long wave at 8000 to 14000 nanometers). This is well above the visible light wavelengths of 400 to 700 nanometers. Lights and other relatively hot objects are very evident, but as a result of their heat, and not their light emissions.
Infrared (IR) imagery is often a gray scale picture whose scales (or shades of gray) represent the differences in temperature and emissivity of objects in the image. As a general rule, objects in the image that are lighter in color are warmer and darker objects are cooler.
The heat energy is displayed in the Infrared image using different color pallets to show where the warmer areas are because of the moisture under the roof membrane. These display colors can be in Gray Scale, using a pallet of varying gray colors, Ironbow, using white / yellow and oranges, or Rainbow High Contrast using the spectrum of rainbow colors to indicate where the moisture is located.
Cool Roofs or Single-Ply Roofing Systems
Roof emittance is the characteristic of how effective the roof material will radiate the heat that is stored in it based on the materials used in the roof membrane. Although cool roof materials are rated to have a high emittance, building owners should remember that this value is an average emittance value considered in a laboratory under ideal conditions and at a vertical viewing angle.
During an infrared roof inspection, smooth-surfaced roofs can be quite reflective to a thermal imager due to the low viewing angle that is usually associated with inspections performed on foot from the roof surface. This condition is most severe on cloudless nights when atmospheric humidity levels are low.
The single-ply roof systems such as EPDM, TPO, PVC and reflective coating operate at a lower temperature thermal sensitivity and the wave length of the imager becomes a more important factor when choosing an inspection firm to conduct these inspections.
What Happens During the Inspection?
Our high-resolution Infrared Thermal Imaging cameras, find the trapped moisture as shown in the image. Wet areas are identified and marked to show exactly where tactical repairs are to be made. By marking wet areas directly on the roof, they can be seen by building owners and roofing contractors after the survey is performed. Often, we find that the infrared survey shows is it is not necessary to replace an entire roof that only a few sections are “wet” and repairs can be made to only these areas.
THE BENEFITS OF COMMERCIAL INFRARED THERMAL ROOF INSPECTIONS
There are important benefits of commercial infrared roof moisture inspections that building managers should keep in mind. Low slope, insulated and flat roof systems, like anything else, need to be maintained to properly protect your capital investment. Frequent yearly IR roof Inspections should be done not only for your own knowledge but also to comply with Roof Manufactures Warranty.
Here are some of key benefits of using our infrared roof inspection service:
1. INFRARED THERMAL ROOF SCAN IS NON-DESTRUCTIVE
Infrared Thermal Scanning is nondestructive. However verification of the marked areas of wet insulation on the roof need to be confirmed followed up by moisture probing meters or core sampling.
Thermal imaging of flat insulated roofs with an infrared (IR) camera quickly and accurately identifies areas of a roof that may have been compromised long before any ill effects are discovered inside a building.
2. EARLY INTERVENTION – REDUCE OVERALL MAINTENANCE COST
By performing regular roof scans you’ll be able to intervene early, before a small problem becomes a large one. And building owners will be pleased to reduce the overall cost of roof maintenance.
3. INFRARED THERMAL ROOF INSPECTION IS COST EFFECTIVE
When compared to dealing with a catastrophic loss of a failed low slope, insulated or flat roof, annual IR roof thermal imaging scan and preventive maintenance is a clear winner.
Another cost related benefits is that a properly maintained roof will lower your energy costs. Wet insulation isn’t as effective as dry insulation.
ADCO Roofing and Waterproofing is prepared to help you stop roof leaks, save you money and give you options to a full roof replacement. Call us today at (800) 773-7663 for more information.