As the 2002 chairman for the Air Conditioning Contractors of America (ACCA), Jim Hussey used to meet and speak with contractors and insurers across the United States. The No. 1 topic for members was always the same: What is ACCA doing about the shrinking markets and rising costs for mold, environmental, and liability insurance?

"The unanimous response from the insurance industry was quite predictable," said the president of Marina Mechanical, San Leandro, Calif. "They said, ‘Coverage for liability related to mold and moisture will be increasingly difficult to obtain, or even to maintain, until HVAC contractors can be successfully defended against claims of negligence.'"

In his eyes, negligence occurs when a service provider fails to perform to a recognized standard of care.

"The next question was obvious," said Hussey. "In the absence of any accepted standard of care for moisture and contaminant management in residential and commercial buildings, who might be the best qualified to provide guidance for HVACR contractors? The answer was equally obvious, the Air Conditioning Contractors of America."

The wheels began turning.

Raising The Bar

To that end, Glenn Hourahan, ACCA's vice president of Research and Technology, was asked to prepare a program and model by which HVACR contractors could demonstrate a level of performance that was in accordance with recognized industry practices in the design, installation, and maintenance of HVAC systems.

"Thankfully," said Hussey, "Glenn and his team were up to the task."

The end result is the recently released Good HVAC Practices for Residential and Commercial Buildings: A Guide for Thermal, Moisture and Contaminant Control to Enhance System Performance and Customer Satisfaction. In addition to Hourahan, Bradford A. Penney, J. D., and James Woods, Ph.D., P.E., were involved in preparing the content. Penney is the associate director and manager of Public Policy, Communications and Outreach of The Building Diagnostics Research Institute (BDRI) in Chevy Chase, Md. Woods is the executive director of BDRI.

"We believe that this guide is but another step for ‘raising the bar' and helping to position HVAC contractors with the knowledge and tools to ensure building comfort systems are properly designed, installed, and maintained," said Hourahan. "Another step is to continually get the ‘quality message' out to the appropriate venues."

The document is intended to serve as a basic reference for contractors and designers, with citations to relevant ACCA manuals, American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) standards, and other technical sources that help to facilitate "good practices." The first part provides a roadmap that addresses many concerns that customers and insurance carriers have, including humidity control deficiencies (which can lead to moisture and other problems), moisture incursion (which can lead to mold and other problems), and contaminant emission and transport (which can lead to indoor air quality complaints, and potentially to occupant health issues).

In the second part, entitled "Assuring Good Practices," the basics of building diagnostics are introduced and used in order to verify and document the multi-step processes for the new and replacement/retrofit markets.

"The difference between ‘minimum' and ‘good' practices is that the latter enables the contractor to have greater influence on the performance of the HVAC system, from the planning stages through installation, commissioning, and maintenance, thereby reducing callbacks and helping to reduce the risks of liability," said Hourahan.

Differentiate Yourself

In other words, this is a good guide to have. It is attainable through ACCA ( Following its steps is highly encouraged. After all, in today's litigious environment, contractors are increasingly being held accountable for mold and moisture problems that, in many cases, may not be directly related to the HVAC system. Following the steps in this guide should help one's legal stance and perhaps assist in keeping insurance premiums low. More importantly, by following this guide, a contractor is better assured that the building HVAC should operate as designed.

Mark Skaer is editor-in-chief. He can be reached at 248-244-6446, 248-362-0317 (fax), or

Publication date: 11/03/2003