Infrared thermography has quickly become an incredible, diverse tool for the home inspection industry over the past several years. With it's ability to see things that the naked eye might not be able to detect, it enhances our chances of finding problem areas quicker and easier than ever before. This technology is basically used as a non-contact, temperature-measurement tool over larger areas. Smaller moisture meters are always used as well to back up anything that could be concerning. With that being said, we have both invasive and non-invasive tools. We don't necessarily like to probe these areas but certainly will if need be.
There are a few misconceptions about IR cameras and how they work that should be cleared up so you have an idea why you should choose an inspector that includes this service.
Infrared does not mean x-ray
First thing we should know about infrared cameras is what they really do. These cameras translate heat signatures of objects into colors on a gradient scale, with higher temperatures appearing as light or warm colors, and lower temperatures or even wet areas appearing as darker, cooler colors. The heat variations that are displayed is how we interpret problem areas. Areas of moisture that could be from a leak can cause damage to structural components or worse, microbial growth, can be located based on apparent temperature.
In no way is the camera able to see through any material. Every object warmer than absolute zero emits infrared radiation, which is invisible to the naked eye but is read by the camera. This is how we're able to detect those problems and even some past problems that may have been cosmetically repaired. If you're attempting to hide a leak behind a wall and you repair the wall but not the leak, the problem is still there! The wet, cooler area behind the wall can usually still be caught by the camera and moisture meter.
Essentially, it's ability to read heat as color and display that information for you to easily understand is what makes it so powerful.
Radiation and Emissivity
Emissivity is how much a material will radiate heat as it cools down. The emissivity of an object is dependent mainly on its surface qualities and the materials of its composition and construction. Non-metals and opaque objects with rough surfaces generally have higher emissivity. Pure, smooth, un-oxidized metals and objects with shiny, reflective surfaces have lower emissivity. Objects with low emissivity can still be examined through thermal imaging but special care should be taken to ensure that such images are interpreted correctly. For example, images of reflective surfaces may be affected by a hot light bulb elsewhere in the room. This could be misread as a temperature difference in the area being viewed. Taking into account the emissivity of objects being viewed, and scanning areas from different spots and angles can help ensure accurate interpretation of the thermal images.
To keep this a shorter read than it could be, we'll close by saying this... In the inspection industry IR cameras are used to gauge what's called "apparent" temperature. Because of the varying levels of emissivity and all the differing materials and areas in a home, as well as other variables that can influence data, such as wind and weather, the "exact" temperature of an anomaly can be tricker to determine with infrared by itself. This is why the most common reason for employing thermal imaging during an inspection is to simply locate and document the problems.
For example, a dark area in the thermal image of a ceiling may indicate that there is moisture above it. Once this has been observed, a moisture meter can be used to confirm moisture intrusion. The pattern of the wet spot can be documented with the camera, and the area above the ceiling can then be examined through infrared in an attempt to determine the source of the leak.
In a case like this, which is a typical example of how infrared is often used in an inspection, the exact measurement of the temperatures -- the quantitative measurement -- is not relevant. The important thing is that the apparent temperature difference led the inspector to a problem area that could be documented and examined more closely. This makes inspection with an IR camera a qualitative measurement, rather than a quantitative one. Thermal imaging is used to locate anomalies through differences in apparent temperatures, analyze the patterns, and document the issues.
We're confident at Izon with our thermal imaging and know just how important it can be. That is why infrared scans of your investment are included in the price of our General Home Inspection. If you would like an Infrared Inspection only, no worries! We offer those as well. For more information on pricing and scheduling your appointment click here!