The image on the left is a visual image and on the right is a thermal image of the same attic area. The numbers are actual temperatures and there is a scale on the right. The spot marked with 97.9 + is an obvious cooling spot from evaporating water and a leak in the roof. Read all about infrared thermography below.
Infrared Thermography, thermal imaging, is a type of infrared imaging science. Thermographic cameras detect radiation in the infrared range of the electromagnetic spectrum (roughly 900–14,000 nanometers or 0.9–14 µm) and produce images of that radiation, called thermograms. Since infrared radiation is emitted by all objects based on their temperatures, thermography makes it possible to "see" one's environment with or without visible light. The amount of radiation emitted by an object increases with temperature, therefore thermography allows one to see variations in temperature. When viewed by thermographic camera, different temperature objects stand out well.
The appearance and operation of a modern thermographic camera is often similar to a camcorder. Enabling the user to see in the infrared spectrum is a function so useful that ability to record the output is often optional. A recording module is therefore not always built-in.
Thermographic cameras are much more expensive than their visible-spectrum counterparts, and higher-end models are often export-restricted.
In building science and home inspection infrared thermography is useful in detection water, missing insulation and air conditioning leaks. As water evaporates it creates a cooler area and is visible with a thermal camera, aiding in the detection and location of water leaks and sources. Water intrusion and leaks are easier to fix the sooner they are located. Undetected leaks can cause all kinds of issues, the longer left un-repaired the more likely they are to cause significant damage. Insulation in a home keep a home more comfortable and cheaper to regulate the temperature. Many homes have some missing insulation that goes unnoticed for years, costing the homeowner every month in heating and cooling costs. These are just some of the useful places for infrared technology, if your home inspector does not use it he/she may be missing important issues. A home inspection is non-invasive and visual so many issues can easily be hidden