Find home and building energy envelope leaks with infrared cameras by doing it yourself, hiring a professional – or becoming one!
Look as hard as you like, but you can’t readily see if inadequacies hidden in and around walls, ceilings, windows, doors and air ducts are wasting energy, keeping home and building energy costs high. The good news is that discovering building envelope defects is about as simple as taking a photograph – in fact, exactly like taking a photo, but one that allows you to see thermal images that human eyes cannot.
Thermal imaging is the secret weapon in the war against heating and cooling loss that allows building construction technicians to “see what you cannot see,” and the dramatic visual results can be used to greatly improve energy efficiency, according to Peter Hopkins, vice president of United Infrared Inc., a national marketing and training company. Hopkins led a workshop on energy monitoring with infrared (IR) technology for homeowners, business owners and construction contractors at the California Center for Sustainable Energy in San Diego, Calif.
While thermal imaging has been around for decades – in use by firefighters, soldiers, scientists and physicians – its application in the home and building inspection industry has really taken off in the past few years.
Basics of IR Technology
The basics of thermal imaging are fairly simple, if you skip the underlying physics and the laws of thermodynamics. All objects with temperatures above absolute zero (–460° F) produce IR radiation that is invisible to us. At certain levels, IR radiation can be seen without illumination by a process called thermography, which shows variations in temperature with higher temperatures emitting higher levels of radiation.
When viewed through an IR imaging camera, warm objects (yellow) stand out against cooler areas (purple) – remember the movie “Predator”? The monster chased Arnold Schwarzenegger around the jungle, tracking him with alien thermography, and there was that great scene when Schwarzenegger hid in a mud wall. Well, with IR vision the monster would have easily seen him, but that’s Hollywood.
IR cameras can’t see through walls, but they can see anomalies within a wall, under the right conditions. What the camera reveals are thermal patterns that indicate studs, conduits, pipes and other solid objects, but for energy efficiency purposes, you are looking for variations in heat that may be caused by cracks, poor insulation or shoddy construction. You can also locate water leaks, pests and electrical overheating hazards, Hopkins noted, which can help keep such problems from escalating into costly repairs.
Thermographic inspection can be done as either an interior or exterior survey, but interior imaging is more accurate because it reduces the effects of weather conditions. The types of things that are usually found are improperly insulated attic access panels, air leaks at room corners and around windows and door frames, missing or compacted wall insulation, air infiltration at lighting fixtures and a host of other energy-wasting defects. Images can be made in conjunction with blower door testing, during which a panel with a calibrated fan replaces an exterior door and is used to create a small pressure difference between inside and outside.
What are the Costs?
The cost of a basic home energy audit, including thermography, generally ranges from $300 to $500, depending on location and square footage. Your home should be energy inspected once to determine if problems exist and whenever a renovation is planned, Hopkins said. The Department of Energy recommends you should have a scan done before purchasing any house because even new houses commonly have defects in the thermal envelope.
There are 10 to 15 IR camera manufacturers, but the majority are sold by FLIR Systems, Inc. and Fluke Corporation. Cameras come in various configurations, sensitivities and resolution, ranging in price from $3,000-$8,000 for a basic camera to $20,000 for one in the upper mid-level. High-end IR cameras for aerial surveys and other large-scale inspections run as much as $500,000. Rentals are available nationwide via the Internet with basic cameras costing from $125 a day to about $500 a week. Local rental companies may offer better pricing and be sure to check at any community or utility energy centers that might lend them for free. In San Diego, the California Center for Sustainable Energy has three cameras available for two days for free.
Thermal imaging offers a wide range of business opportunities for any home or building professional, Hopkins pointed out. It’s a great inspection tool for everyone from plumbers and electricians to insulation contractors and garage door salesmen, providing irrefutable evidence of existing conditions that may help land the job or make a sale.
For those considering using thermal imaging to get into the home energy inspection business, you should begin by checking local and state regulations concerning training, licensing and certification. Requirements vary greatly from Massachusetts, which demands 75 hours of training, completion of 25 inspections under supervision and an addition 100 under direction, to Iowa, California and Hawaii that have no licensing requirements at this time. There are books and DVDs that offer self-training and a host of classroom and online training and certification programs offered by companies such as the Infrared Training Center and the Academy of Infrared Training.
In today’s world of rising energy costs, it is important to insure that we have the most energy efficient buildings and homes possible. Thermal infrared cameras for energy audits offer a perfectly easy way to detect and, with repairs, eliminate energy loss due to inefficient insulation or poor construction. Learning to use one could also lead to a new career in many areas of noninvasive inspection and detection.