Checking Flat Roofs Inspection Using Thermal Drone
7. 2. 2020
Human body temperature and how to measure it correctly with a non-contact thermometer and thermal camera
13. 3. 2020While flat roofs are common, they can be problematic. Several areas of any flat roof can be the source of a significant structural fault. These areas include the point of the roof’s contact with the attic, as well as its point of contact with drains. Leakage may also occur in weaker areas as the result of improper installation, neglected maintenance, and surface degradation due to insufficient protection of surface layers against weathering.
If a flat roof is exposed to excessive wind loads, it will experience dynamic shocks – severe oscillating motions and that lift unpaved sections. Eventually, prolonged wind exposure can thin the roof and cause leaks. Any water that builds up on damaged roof areas then has an amplified negative effect on the roof’s durability. If water flows through the gaps between insulation panels, under the impermeable thermal insulation, and into the waterproofing system, it will have a very low temperature. This will in turn reduce the quality of the waterproofing system, which can result in the condensation of water vapor within the roof deck, beneath the waterproofing system. In extreme cases, leaking water may also overload the roof deck’s supporting structure.
However, there is a fast, reliable, and simple method to identify flat roof faults. This method comprises the use of a thermal camera, which detects the temperature difference between the dry spot and the penetrating humidity site to reveal the entire range of affected insulation. Depending on the roof’s structure, one may also be able to clearly see how large the affected area is, and thus identify the extent of damage along the fault.
The physics behind the thermographic inspection of roof humidity is straightforward. The moisture-free (dry) part of the roof cools and heats up slower than the wet part of the roof. A thermographic inspection with a thermal camera simply reveals damaged areas by identifying dry spots, since they cool faster than damp areas, which have a higher heat capacity.
Thermographic measurement should, of course, be done under the right conditions to obtain the appropriate thermograms. Thermographic inspections should take place after sunset, as sunlight will heat up the entire roof. In addition, there must be a sufficient difference between daytime and sunset temperatures for the inspection to succeed.