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Bob Brice, president of Cenergy LLC, a home energy performance consulting firm in Des Moines, Iowa, talked to National Comfort Team (NCT) contractors about the energy ratings game at the National Comfort Institute’s (NCI’s) NCT meeting in Clearwater, Fla.
An energy rater is someone who specializes in building science. This professional completes home energy ratings to qualify the property for tax incentives, Energy Star® compliance, utility incentives, etc.
Energy raters usually have limited HVAC knowledge and experience, Brice said. “Make sure your rater knows more about HVAC.” Most are familiar with blower door and duct blaster testing, but they may not perform advanced HVAC performance testing.
VALUABLE PARTNERWhile some contractors may believe that energy raters are after their work, they truly are not, said Brice. The energy rater can be hired by the builder, homeowner, HVAC contractor who wants the extra verification of system performance, or another trade. “More than anything, they just want cooperation,” Brice said. “We’re just trying to get this done.”
Energy ratings are a means to evaluate a new home’s energy soundness, or to create an energy audit for an existing home. These existing home audits represent “50 percent of what we do now,” he said. Energy raters can also perform Manual J, D, and S calculations for HVAC contractors.
Existing home strategies include focusing on the entire house, not just the mechanical room. “Is adding a heat run in the floor above the garage to stop the pipes from freezing really a good idea?”
“A good energy rater can be your best friend,” Brice said.
When it comes to determining a home’s energy consumption and leakage, “We knew there was more to the story than just blower doors and duct blasters,” he said. There were failures with no explanation even after those methods were applied. “We were looking for solutions to problems grounded in simple field logic rather than laboratory theory.”
COMPLETE SOLUTIONSHome Energy Ratings Services, or HERS, gives a more complete picture of how the house is consuming energy. “Like it or not, the house is a system,” said Brice. “You can’t change one thing and not expect anything else to change.” Still, some energy programs, such as Energy Star, do not take into account everything they should about the mechanical system in the home.
“I found NCI and completed their air balancing and CO/combustion certifications,” Brice said. Current and future national energy programs are forcing raters into the HVAC world, he said, adding, “We’re not living in laboratory conditions. Solutions grounded in field options are what is needed. Customers aren’t getting what they’re paying for.”
Pinpointing the cause of a problem, however, is only one-half of the answer. “You must provide solutions rather than just identify problems and walk away.” By partnering with a good rater in your market, HVAC contractors have the opportunity to be a hero, no matter whose “fault” the problem is. “Wrap up a solution in a nice little box.”
“Being able to identify, or at least understand, items beyond the typical scope of work is key.”
Increasing utility costs are influencing consumer behavior more than ever before, he continued. “If nothing else, Energy Star has powerful market recognition. However, it has no requirement for HVAC system testing. Therefore, many times we end up with a false sense of security because we have no idea how the system will actually perform.”
ENERGY CODE COMPLIANCEThe HERS rating is increasingly accepted as demonstrating code compliance on a performance basis, Brice said. It is considered to be a comprehensive building analysis that considers all major energy categories (windows, insulation, air infiltration, heating-cooling equipment, ventilation, and overall building envelope integrity).
Software modeling evaluates anticipated performance compared to a “code” home (IECC 2004.) The HERS index rates how much better than code a home is. It allows for flexibility in design, not limited to specific products or technologies, and estimates energy costs and usage. It is, however, directly related to user input. The garbage in, garbage out (GIGO) rule applies.
It gives credit for “good” design and penalties for “bad.” It evaluates the entire structure (window type and orientation, wall construction and orientation, even siding color, attic insulation, ceiling type, shingle color, air infiltration [blower door test], duct leakage [blaster], and mechanical equipment specs, including fuel types and geothermal well specs).
It requires thermal bypass inspection before the drywall goes up, enabling professionals to catch problems before it’s too late to fix them.
On the negative side, the limited HVAC system testing gives credit based on ARI (Air-Conditioning and Refrigeration Institute) and GAMA (Gas Appliance Manufacturers Association) ratings. “There is no protocol for testing delivered Btus,” said Brice. “The duct leakage method … sometimes ends up giving credit where it is not due.”
In 2006, he said, the 15 percent air conditioner oversizing rule for Energy Star was modified to require documented load calculations (Manual J8), which “can potentially take control away from the HVAC contractor,” said Brice. It heavily favors “tags on the boxes, not measured performance, and can encourage the blame game rather than cooperation.” It also mandates duct blaster testing.
“If the HVAC contractor installs equipment to the Energy Star specs, and then the system only delivers 61 percent of its rated capacity, who gets the liability? Answers range from that darn rater and the HVAC contractor, to the homeowner and the government - They screw up everything, why not this too?”
The answer, said Brice, is to consider becoming a rater or to partner with a rater and understand each other’s business. “View the issues from all points of view. Work together to maximize performance and minimize liability. Prevent the callback by getting it right.
“Leverage new partnerships to leave your competition in the dust.”
Publication date: 04/21/2008