Professionals can use advanced diagnostic equipment, such as blower door, heating system analyzers and duct leakage systems to identify energy-saving strategies in single family and multi-family homes. Provided below are short descriptions of the various tools, as well as some web resources for finding out more information on diagnostic equipment.

• Blower Doors. The blower door is one of many tools, which we use to assess a home for health, safety, durability and energy efficiency. A blower door is a large calibrated fan that is temporarily mounted in a house door to measure the "leakiness" of the house and to assist in finding the location of the leaks. Modern blower doors have variable speed fans so that the pressure in the house can be adjusted, and they have door-mounting frames so that the fan can be sealed tightly into the door jamb. In order to measure the leakiness of the house, the blower door measures both the airflow through the fan and the pressure difference between the house inside and outside.
  
  Two examples of manufacturers that produce blower door equipment are the Energy Conservatory and Infiltec. Specific equipment details are available through their websites.
  
  
• Duct Leakage Testing. With the blower door equipment, professionals can also conduct a duct pressure test to see the amount of air leakage through holes in the ducts, another energy consumer. Typically, a digital tool is used while the blower door is operating and identifies if ducts are leaky. Identifying duct leakage is an important measure for improving energy efficiency, health and safety, and comfort. Leaky ducts cause heating and air conditioning units to work harder, causing higher energy bills. The Energy Conservatory manufactures several types of duct system equipment.
  
  
• Thermography. Infrared cameras have been successfully used as a building diagnostic tool for over a decade. From verifying insulation integrity to finding thermal bridges and air leakage sites, it is a useful tool for diagnosing hidden performance problems. Unfortunately, either infrared cameras have been too expensive for most building performance professionals, or they have lacked the thermal sensitivity to provide reliable images.
  
  Both Linear Labs and the Energy Conservatory websites provide additional information on specific equipment.