Infrared Thermal Imaging
Within their nest, workings and leads, termites create a climate which may be hotter than its surroundings. Infrared Thermal Imaging passively reads the temperature differential of the surface it is pointed at so that termite problems may be detected without disturbing walls, possibly before termites create significant damage. When used by properly trained inspectors, large areas can be scanned quickly to identify and target areas of interest.
Thermal Imaging is also very useful in identifying dampness, moisture ingress and ventilation problems.
The Thermal Imaging Myth - Busted
While conducting thousands of inspections, we have researched numerous technologies. Several years ago we adopted thermal imaging to enhance our inspections.
Unfortunately, there have been outrageous thermal imaging claims from unscrupulous operators which has created widespread missconceptions about the capabilities of Thermal Imaging.
Thermal imaging is neither a magical device nor a guarantee of finding hidden defects and termite activity despite the claims of some inspectors who mislead people into believing that thermal cameras can "see" inside walls. Basically, a thermal imaging camera is a useful addition to, but not a substitute for the knowledge, skills and experience of a good timber pest inspector.
Thermal imaging does not "see" inside walls unlike an X-ray, CAT Scan or MRI although you may have seen thermal images showing the framing inside walls. This is misleading as the darker lines of the frame are visible because the frame acts as a heat sink draining heat from the wall sheet and appearing as a dark spot. The frame lines on the image are actually colder sections of wall sheeting as a result of the heat being drained away from the surface of the wall sheet and not the frame itself being "seen" through the sheet.
Thermal imaging simply provides a temperature reading across a surface, building up a picture from thousands of temperature measurements in its field of view. It's also useful in displaying patterns of moisture which evaporates and cools surrrounding material. Conversely, as termites maintain a constant temperature between 28 and 32 degrees Celcius in their workings, if there are enough of them and the ambient temperature is cooler, termite activity presents as a hot spot.
The detection of defects and timber pest activity using thermal imaging is not a simple process and requires knowledge, skill, experience, and training. The process must take into account the climate, the current weather, the structure's use and occupancy, the time of day, the type of construction, heating and air conditioning, plumbing, wiring, construction materials, surface finish, and even colour.
When applied to a surface a moisture meter may detect excessive moisture in plaster sheeting, masonry or timber walls, indicating the presence of conditions that attract termites and cause fungal decay even when there are no outward signs of damage. A moisture meter will also detect moisture from leaking pipes or rising damp. All high moisture readings should be investigated to determine the cause.
Where termites are suspected to be present behind walls, their presence may be confirmed visually by drilling a small hole and inserting a ‘Boroscope’ which illuminates the wall cavity. The inspector views the inside of the cavity via the eyepiece, rotating the boroscope to get a 360 degree view.
Note this is not done as part of a pre-purchase inspection but as a followup further more invasive inspection when termites are suspected.