Avoiding Unintended Consequences in Home Performance

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In our area, the ductwork, HVAC equipment and water heating equipment are most often in the attic. We have virtually all flex spider systems. Wall chases are frequently used for returns and supplies. Point a thermal camera on a wall and you are likely to see at least half the wall and the ceiling light up. The top plates are rarely sealed. In fact, we almost never see anything sealed, hence the numerous complaints of black streaks on walls and “mold” on grills. Hopefully, you have more hospitable conditions.

No matter where you are, every change you make to a home, makes other changes you may not have considered and never intended. Hopefully this helps you avoid some of the unintended consequences that can harm your client and your business.

1. Don’t blindly follow rebate incentives. Don’t perform a measure based on the highest rebate potential, without considering the consequences of doing so. Instead, pay attention to whether each measure will help or hurt that particular home taking into account ALL the information the home is trying to give you. Just because the client CAN get a $200 rebate for duct sealing, doesn’t mean the ducts should be sealed.

2. Use any “clipboard audit” as a suggestion, not gospel. Pay attention to the clipboard audit, especially if you are working with incentives, as a starting point. However, don’t ignore your better judgment or more rigorous testing. When you find a conflict, bring it to the attention of the client, auditor and the program. No clipboard audit is a substitute for a thermal camera, air flow hood, static pressure meter, blower door test and/or your knowledge about HVAC/HP.

3. Start with proper airflow before sealing the ductwork. Don’t even think about duct sealing before measuring for proper air flow through the system on both the return and supply sides.

If you have insufficient air flow, sealing the ductwork will put too much pressure on a system that is already starving for air and may kill the equipment. Worse than that, the air still has to come from somewhere and the house will pull from any other place it can find to provide it. The home will be even less comfortable, healthy and efficient than it was before you performed the work. If the client does not choose to correct the air flow issues, don’t seal the ductwork (unless you have a full disclaimer). Sometimes, it is the ONLY reason the system works at all.

4. Pay attention to other “systems” that rely on home performance “defects” to operate. Sealing the ductwork, stopping air leakage, separating the home from the attic and fully insulating the attic floor sounds like a great idea. However, what effect will those changes have on other “systems” in the “new” attic? Does your client face an increased risk of pipes freezing in the winter now that the home, ductwork and leakage no longer heat the attic? What about the combustion appliances? What will happen when they can’t steal air from everywhere? How effective will the water heater be in a colder attic?

5. Don’t rely on or spread HVAC/HP myths. For example, don’t encourage clients to block off vents in unused rooms or close the doors without understanding the impact of those “conditioned space manual dampers” (as National Comfort Institute calls them) on the home and the equipment performance. This kind of advice can undo all the good the client paid to achieve.

6. Stay up to date with the latest information, training and tools. HP/HVAC are not static fields. Don’t rely on what you learned five years ago. These fields are constantly changing and improving. Recognize when you are in over your head. Professionals get the information, training and tools they need. If you don’t, you might as well let the homeowner DIY the project.

7. Step back when faced with client concerns to look at the whole picture. For example, when the client highlights a dust problem, most focus on filtration. Others think duct sealing. Meanwhile, they ignore the 40 recessed lights that are: non-IC rated; not sealed; drawing cold air in the home in the winter and hot air in the summer and unfiltered filthy air all year long. To control dust, you must at least look beyond just the filtration into other areas that contribute to unhealthy air (and discomfort) in the home. This only happens when we step back and take an educated global approach.

8. Help clients plan ahead to achieve the best results. Be a proactive partner with your clients, especially those with working, but aging equipment. Rather than focusing on the equipment first, address insulation, ductwork design/modification/replacement, air sealing and other HP improvements that reduce the load the home requires and guard against unintended consequences. After those modifications, premium full system installations make sense. Without them, clients are not receiving the full potential of their investment in new equipment. In fact, they may not be receiving much benefit at all.

9. Remember that there are no one size fits all HP solutions. The home dictates the proper solutions, not the other way around. No matter how awesome the technology, not everything you can do should be done. For example, foaming the attic to bring the equipment into the conditioned space of an existing home may sound like a good idea. However, you want to take into account the possible humidity issues it may create and fashion a solution for it … before it starts raining in the attic.

As professionals, we strive to provide the very best service to our clients. However, if we do not stay on top of our own education and guard against unintended consequences, we may discover we have caused the client more harm than good.

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Posted In: Building Performance, Residential Buildings