Building performance, HVAC go hand-in-hand
The HVAC contractor must handle all aspects of home and building envelope air sealing, insulation, and health and safety as a one-stop resource
Carol Fey | Sep 01, 2010
When asked what is the best way to increase the efficiency of any HVAC installation, including hydronics, Dan DePontbriand, contractor at Mountain Air said, "Insulation and building sealing ... the challenge of heating efficiency is keeping the heat inside the building envelope once you've delivered it."
DePontbriand installs both hydronic and forced air systems and believes that there is no difference between the two when it comes to looking at the whole building as a system. Traditionally, air sealing, weatherization and insulation have been a separate industry from HVAC.
But the fact is that no matter how efficient the equipment that a heating or air conditioning contractor installs, if the building doesn't perform right, it's the HVAC contractor that gets the return calls to fix the problem. That's the case even when the problem is air leakage to the outdoors or lack of adequate insulation. Escaped tempered air, whether the heat source is a boiler or a furnace, subtracts from the efficiency and comfort of the heating job. That's why the HVAC business is becoming the building performance business. It's the building as a system, not heating or air conditioning equipment, which determines total efficiency and comfort.
"Who is in a better position to evaluate the need for sealing, weatherization and insulation than a heating contractor?" asked Gary Southern of Specialty Comfort Enterprises, a company which teaches HVAC contractors to treat the building as a system. "Like no other industry HVAC contractors care for home and building owners and their comfort, energy savings and efficiency, peace of mind, health and safety. So the HVAC contractor must handle all aspects of home and building envelope air sealing, insulation, and health and safety as a one-stop resource."
How does a contractor get into the building performance business? DePontbriand started as a HVAC new construction contractor. Repeatedly called in to solve temperature comfort problems rooted in problems outside HVAC, he decided to take control of the situation. He learned to do energy audits by attending distributor-sponsored training sessions. He became educated on how to do load calculations (also called heat loss calcs), the basic determinate of correct equipment sizing. Then he learned how to do the building performance industry standard "blower door test," which locates sources of air leakage by pressurizing the home or building. Finally, frustrated with working with subcontractors, he learned to install insulation and perform building air leakage sealing.
The building-as-a-system approach to insulation and sealing is quite different from that of many insulation contractors. First difference is the concept that identifying and sealing air leaks are more important than installing insulation. But without performing a blower door test, those leaks can be impossible to find. An example is the air leakage around ceiling can lights.
Second is to identify where insulation is lacking, rather than randomly blowing it into a building. An infrared camera can find exactly where insulation is needed. For example, there may already be plenty of insulation in almost all of the attic, but it may be completely missing in a hard-to-reach area or it may be uneven.
When it comes to becoming certified in building performance, there are a number of certifications to be had. DePontbriand attended training provided by the Comfort Institute, www.comfortinstitute.org, and became certified by the Building Performance Institute.
"But the real way to learn this is by doing it," DePontbriand said. "Start with your own home and that of everyone you know. Do load calcs and blower door tests. If it's forced air, do duct blaster tests. The duct blaster makes air leaks as apparent as puddles of water do for hydronics. Climb through attics, find air leaks, fix them and see how that makes a difference in equipment efficiency."
Eight years into being a building performance contractor, DePontbriand believes that it definitely was the right business decision. Whether the job is new construction or retrofit, he takes the initiative to educate the owner about the total building performance.
"People don't care about equipment efficiency … they care about comfort," he said. "Making sure I offer everything having to do with this means that I control the end product. And that offers more revenue generation."
The following are reasons for a HVAC contractor to recommend sealing and insulating:
"To survive in the future, the HVAC contractor needs to be willing to change his business model," said Dave Schrock, DePontbriand's distributor for both HVAC and building testing equipment. "Selling the box, that is HVAC equipment, is secondary to providing what the owner is really interested in: health, safety/comfort, efficiency and durability."