|
Professional energy auditors may use thermography—or infrared scanning—to detect heat losses and air leakage in building envelopes. How It Works Thermography measures surface temperatures by using infrared cameras. This thermal imaging camera sees light that is in the heat spectrum. Images on the film record the temperature variations of the building's skin, ranging from white for warm regions to black for cooler areas. The resulting images help the auditor determine whether insulation is needed. They also serve as a quality control tool, to ensure that insulation has been installed correctly. Thermographic scans are also commonly used with a blower door test running. The blower door helps exaggerate air leaking through defects in the building shell. Such air leaks appear as black streaks (in winter, white streaks in summer) in the infrared camera's viewfinder. Infrared scanning allows energy auditors to check the effectiveness of insulation in a building's construction. The resulting thermograms help auditors determine whether a building needs insulation and where in the building it should go. Because wet insulation conducts heat faster than dry insulation, thermographic scans of roofs can often detect roof leaks. The most accurate thermographic images usually occur when there is a large temperature difference (at least 20°F [14°C]) between inside and outside air temperatures. In northern states, thermographic scans are generally done in the winter. In southern states, however, scans are usually conducted during warm weather with the air conditioner on. In mixed climates, scans can be performed during both the heating and cooling seasons. Images Copyright © FLIR Systems
|
