BPI Certified: The Building Performance Institute (BPI) is the nation's leading building science accreditation organization. This organization teaches the "house as a system" philosophy - which looks at a building's various components (building envelope, attic, basement, combustion equipment, ventilation sources) and the interrelationship between them to maximize a home's performance. This approach leads to greater energy efficiency, but perhaps more importantly to buildings that simply work better. A home that has been analyzed and upgraded from a whole-house standpoint is more durable, healthier, more comfortable, and more energy efficient. For more information about BPI's standards, take a look at their Technical Standards for Building Analysts (PDF).
We had a great experience with Energy Reduction Specialists! I respect and appreciate their expertise and professionalism. They were patient in answering my questions and skepticism and did the job right the first time. My house is noticeably comfortable and look forward to the better comfort this summer when the A/C is on.