Thermography

Our auditors use thermography—or infrared scanning—to detect thermal defects and air leakage in building envelopes.

How They Work

Thermography measures surface temperatures by using infrared video and still cameras. These tools see light that is in the heat spectrum. Images on the video or 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.

A thermographic inspection is either an interior or exterior survey. The energy auditor decides which method would give the best results under certain weather conditions. Interior scans are more common, because warm air escaping from a building does not always move through the walls in a straight line. Heat loss detected in one area of the outside wall might originate at some other location on the inside of the wall. Also, it is harder to detect temperature differences on the outside surface of the building during windy weather. Because of this difficulty, interior surveys are generally more accurate because they benefit from reduced air movement.

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 the infrared camera's viewfinder.

Because of the advanced infrared technology, there are many applications where infrared scanning can be performed. A few of these are:

During Blower Door testing as an addition to the energy audit to quickly and precisely locate and document air leaks. The blower door helps exaggerate air leaking through defects in the building shell. It appears as dark streaks in the infrared camera’s viewfinder.
Checking the effectiveness of insulation in the building’s construction. A thermo-gram can help determine whether a building needs insulation; and where in the building it should go. Because wet insulation conducts heat faster than dry insulation, thermal scans of roofs can often detect roof leaks.
Electrical and mechanical systems benefit from thermo-grams to reveal poor electrical connections creating high resistance temperatures on a terminal or increased wear shown as excess heat build-up, making thermal imaging a valuable tool for preventive maintenance.
Before selling or purchasing a house; even new houses have defects in their thermal envelopes.