The health of a building directly affects its habitability, energy consumption, and even safety. Traditional building inspection methods are often time-consuming and labor-intensive, and it is difficult to find hidden problems. The emergence of thermal imaging cameras for building inspection has brought about a revolutionary change in building inspection. It can quickly image without contact, convert heat information invisible to the naked eye into intuitive thermal images, and make the potential dangers of buildings nowhere to hide.
This article will comprehensively analyze the major applications of thermal imaging cameras for building inspection, from thermal defects to safety hazards, all in one go.
4 Major Applications of the Thermal Imaging Camera for Building Inspection
1. Detecting Exterior Wall Hollowing
Exterior wall hollowing refers to the phenomenon where a gap forms between the exterior wall finish and the structural layer (concrete or brick wall), similar to skin peeling. This not only affects the building’s appearance but, more importantly, reduces its durability and safety. It can even lead to wall detachment, posing a safety hazard.
How can we quickly and accurately detect these hidden problems? Infrared thermography provides us with an effective solution.
How Does Infrared Thermography Detect Wall Hollowing?
Air is a poor conductor of heat, with a thermal conductivity significantly lower than building materials such as concrete and brick. When there is a hollow area in a building’s exterior wall, it acts as a region with higher thermal resistance. Due to this thermal resistance difference, when heat transfers from the exterior wall surface to the interior, “heat accumulation” or “heat loss” occurs in the hollow area, resulting in a temperature difference between the hollow area and its surroundings.
Hollow areas typically appear as different colors on a thermal image, forming “hot spots” or “cold spots”. Inspectors can determine the location and size of hollow areas based on these findings.
2. Detecting Water Infiltration of the Building
Water infiltration and dampness are common quality defects in buildings. Especially in rainy and humid areas, rainwater may infiltrate into cracks in walls or roofs and then stay in the building materials, causing the building to become damp. In mild cases, it may stain the interior decoration and affect the visual experience. In case of long-term leakage, the wall surface will become moldy and deteriorate, leading to mold growth, and it may also corrode the structural components, endangering the safety of use and shortening its service life.
Therefore, it is crucial to timely detect water infiltration and determine the location of moisture hidden in the building. The infiltration source and path in general buildings are usually hidden, which makes them difficult to find by conventional methods.
So, how can we detect water infiltration issues early? A relatively simple method is to use an infrared thermal imager.
When water infiltrates a building, such as in the roof, walls, bathrooms, or kitchens, the specific heat capacity of water being higher than that of building materials causes a temperature difference between the leaking area and the surrounding dry areas under the same thermal radiation conditions. Infrared thermography visualizes these temperature differences in various colors. The infiltration area, due to the presence of water, usually exhibits a lower temperature, forming a “cold spot” that contrasts with the surrounding area.
Based on this principle, maintenance personnel can use infrared thermography to accurately and quickly detect the location of water infiltration. By examining suspicious areas identified in the thermal images, the cause of the infiltration can be further determined, allowing for targeted repairs.
3. Electrical Equipment Fault Detection
In modern society, whether it’s household electricity or office equipment, all heavily rely on a stable and reliable power supply. However, during the long-term operation of power systems, various faults are inevitable. It’s especially important to be vigilant about early faults that possess “concealment” and a “latency period“, such as poor contact, aging lines, and overload. These faults often manifest as abnormal heat generation in their early stages, but due to their hidden nature, they are often difficult to detect with the naked eye. However, if not addressed promptly, these small hidden dangers can evolve into major disasters, leading to major disasters, including fire risk, equipment malfunction, and system paralysis.
Therefore, it requires the establishment of a set of scientific, accurate, and operable electrical safety testing methods. Infrared thermal imaging happens to be one of these methods, even identifying hidden faults earlier and more accurately. Without needing to touch electrical equipment or shut off the power, they can perform a rapid, comprehensive scan of electrical equipment, visually presenting temperature differences, and precisely locating faults.
How Do Infrared Thermal Imagers Detect Electrical Equipment Faults?
During the operation of electrical equipment, when faults such as poor contact, insulation aging, or overload occur, the fault point will generate abnormal temperature rises due to increased resistance. Infrared thermal imagers utilize this principle to capture the infrared energy radiated from the surface of electrical equipment and convert this invisible infrared radiation into perceptible thermal images. In the thermal image, different colors represent different temperature levels, thus intuitively presenting the temperature differences on the equipment surface.
Maintenance personnel can perform rapid scans of energized equipment in operation without a power shutdown. Inspection focus is typically placed on critical heat-prone areas such as copper busbar joints, switch contacts, and cable connections within distribution cabinets for a comprehensive and efficient investigation. Through comparative analysis of the thermal images, abnormal hot spots can be precisely identified. These hot spots often indicate potential fault hazards.
Furthermore, by utilizing professional temperature measurement and analysis software, technicians can further analyze temperature change trends and provide early warnings of potential equipment risks. This enables preventative maintenance, allowing for the timely elimination of hidden dangers, preventing equipment fault escalation, and ultimately ensuring the continuous and stable operation of the power system.
4. Termite Prevention and Control
Due to the extensive use of wood components that have not been treated for termite prevention during construction and decoration, as well as the relatively humid environment on site, the necessary moisture for termite survival is provided, making this part of the building and wood components extremely vulnerable to termite damage, thereby threatening the safety of the building itself.
Termites have the characteristic of being highly concealed. Traditional manual termite control methods relying on “seeing, listening, probing, and prying” are costly, destructive, and do not address the root cause. Using a more professional infrared thermal imager for non-destructive testing of building safety and termite control methods is more scientific, intuitive, and efficient.
How to Use an Infrared Thermal Imager for Termite Control?
(1) Detecting Hidden Structural Issues
Investigating Indoor Water Leakage Sources: Termites need ample water sources for survival, and indoor water leakage areas often become their preferred habitats. Infrared thermal imagers can quickly scan indoor walls, areas around pipes, and other regions to detect abnormally low-temperature zones. These low-temperature zones usually indicate temperature drops caused by water evaporation, suggesting potential seepage or leakage problems. Indoor water leakage sources can be effectively investigated and addressed with infrared thermal imagers, enabling timely repairs and rectifications.
(2) Screening Termite Nests
Termite nests typically maintain constant temperature and humidity, with humidity usually higher than the surrounding environment. The higher humidity inside the nest will cause moisture evaporation, causing a temperature difference between the nest and the surrounding walls. In warmer climates or during the summer, termite nests tend to be cooler than the surrounding wall temperature. Conversely, in colder regions or during winter, termite nest temperatures are typically warmer than the ambient temperature.
Conclusion
Infrared thermal imagers, with their outstanding advantages of non-contact, rapid imaging, and visualized thermal information, are becoming indispensable key tools for modern building inspection. Whether it is building thermal performance evaluation, safety hazard investigation, or energy consumption optimization management, thermal imagers can provide strong support to help create a safer, more energy-efficient, and more sustainable building environment.
