Home Performance and Building Science

The performance of a home is a measure of how well the home's systems work together.  Home Performance is a whole house perspective which utilizes diagnostic testing techniques to measure the building envelope for air-tightness, identify sources and locations of heat loss, test ducts and delivery systems for air leaks, and test combustion appliances for efficiency and safety.  These diagnostic tests assess the interactive components of the system to understand the way the structure works and operates in order to recommend the best way to improve it.

If one asks an insulation contractor, a window salesman, and a heating specialist the best way to warm up a cold drafty home, one will get 3 different answers.  Home performance brings the trades together to focus on the whole house as a system.  Without diagnostic testing of a drafty home, it is hard to know with certainty why its occupant is uncomfortable.

Home performance diagnosticians and contractors are trained in building science, and use a scientific diagnostic approach to problem solving.  Experience and observation, combined with pressure diagnostics, infrared imaging, and combustion analysis, allow home performance professionals to diagnose and correct the most challenging building performance problems.

The real difference between the remodeling industry of yesterday and the home performance industry today is that now, the specialty trades work together toward a common goal of energy efficiency.  A home performance contractor’s willingness to "sweat the small stuff"  the customer never sees, like air sealing, insulation, and ductwork, and to use diagnostic equipment during and after construction is the key to realizing deep energy reductions.

The core concept is an emphasis on utilizing results from performance testing to recommend improvements and then measure the results of those improvements. Performance testing also provides assurance to the customer that they have a safe, comfortable, durable, and efficient building when the work is complete.

Home Performance Tests

Blower door: A Blower door measures pressure differentials and determines the rate of air leakage of a house.  A blower door used while air sealing and during weatherization will determine the effectiveness of these procedures.  Used in combination with other inspection tools such as an infrared camera or a smoke pencil, a blower door can help identify the location of air leaks. A blower door used in combination with a duct blaster can quantify the amount of duct leakage to the outside of conditioned space.

More information about blower doors:

• Blower Door Basics by Martin Holladay

• History of the Blower Door, Home Energy Magazine

• Minneapolis Blower Door Brochure, Energy Conservatory (PDF, 512 KB)

Infrared Imaging: Infrared Thermography uses a special camera to show temperature differences on surfaces.  This is a highly effective means to detect heat loss and identify location of air leaks. 

This technology can also be used to inspect electrical connections and components for excess heat, and can be used on mechanical systems to detect heat from increased friction.

• Thermographic inspections: How they work

Duct Testing:

• Minneapolis Duct Blaster Brochure, Energy Conservatory (PDF, KB)