Thermal Scanning
Thermographic roof surveys are a non destructive method of determining the degree to which a roof system has become moisture contaminated. This technology can be valuable to the building owner or manager in that it can often catch small leaks before significant damage is done to the roof system, thus avoiding costly roof replacement not to mention the consequential damage to the building and contents.
Thermography roof surveys produce a complete picture of a roof surface. Variations in surface temperatures are precisely delineated and identify potential areas of wet insulation. The virtually non-destructive testing system provides a confirmation of a sound roof as well.
The Thermal Scan provides the client an assessment of the condition below the membrane to determine if any moisture is present.
The benefits are:
- Determine extent of damaged area.
- Decide whether to replace or repair.
In searching for wet insulation, the operator of an infrared camera is looking for temperature variations on the roof surface. However, there are numerous reasons why temperature variations might occur on a roof. Some of the more common reasons are:
- Hot air exhaust onto a roof from a fan or vent.
- Heaters suspended just below a roof with minimal insulation.
- Hot rooms below the roof (boiler room).
- Differences in the amount and type of insulation in the roof.
- Wind shelter and radiated warmth from walls of higher portions of the same building.
- Significant differences in the thickness of the built-up membrane.
- Wet insulation.
From the above list, it is obvious that locating a thermal anomaly does not necessarily mean that wet insulation has been found. Core samples and moisture probes of the roof membrane and insulation are necessary to verify that wet insulation has been detected. The optimum time to locate these differences with a hand held infrared camera is at night when solar interference is eliminated.
On a summer day, the surface of a roof is heated by the sun. This heat is conducted away from the roof surface by wet insulation and stored there. Dry insulation resists penetration of solar energy and has little energy storage capacity. Because of these conduction and storage differences, the roof surface is hotter over dry insulation that over wet insulation when the sun is shining.
As the sun goes down, the entire roof cools. Dry insulation cools rapidly. Since wet areas have more energy stored in them as hot water, they cool more slowly. At some point, the roof surface over the dry area will be the same temperature as the surface over the wet area. Thereafter, the surface over the dry area becomes colder than the surface over the wet area.
We utilize state of the art FLIR thermal imaging equipment and Delmhorst moisture sensing instrumentation to ensure the most accurate analysis available in the industry.