Like the inspection that utilities used to call an “energy audit,” the home-performance assessment can reveal whether your home is pouring expensive, conditioned air into the Great Outdoors through leaks like cracks and gaps in walls, around windows and doors, and through the roof. It also will clue you in to easy fixes that will cut your energy bill, like adding exterior shade screens to sun-struck windows or switching from incandescent light bulbs to compact fluorescent lights.
But the home-performance auditor doesn’t stop at pointing out your home’s energy flaws. After conducting tests at your house, the energy specialist will determine how a problem—or a solution—in one area of the building might affect the performance of another—good or bad.
Examples: The reason an air conditioning system kicks on too often might be an insulation failure in the attic. Re-attaching or adding insulation could solve the a/c problem and save you from replacing the system. Likewise, a homeowner might figure a new air conditioner will stop a room with a sun-drenched window from getting too hot during the summer. But the auditor might reason that adding an exterior shade screen or planting a leafy tree outside of the window might be a better—and cheaper—fix.
The "old" energy audit looks at stand-alone problems. The home-performance assessment evaluates the whole house as a single system and addresses the impact that changing one thing could have on the rest of the house.