Conversation with an Energy Auditor: John Porterfield
Oak Park, Illinois
What is the biggest overall misconception that homeowners have about energy efficiency?
I offer five, though there are innumerable misconceptions:
First, the economic return of energy-use reduction lacks merit. Let's compare to a similar investment – a secure and lasting asset that appreciates in value and provides immediate, tax-free income. An efficiency package can equal the return from the comparable across-the-counter investment, and some efficiency work will out earn the comparable investment by a factor of times.
Second, air tightening buildings is a threat to human health and will reduce building durability. We agree that buildings have to breathe, but more specifically, we say air tight and ventilate right. Ventilation of residences, like commercial buildings, should be provided by a fan. This allows pollutants to be drawn out of the building at their source. Intermittent operation of the fan will assure outdoor air in accordance to ventilation standards. Air leakage is not ventilation. The exterior of the building must allow moisture to evaporate. Air tightening at interior surfaces is usually effective to assure durability of construction. Air tightening, then, is a strategy to have effective fan-forced ventilation while avoiding moisture in construction and possible mold, rotting, brick deterioration, etc.
Third, windows are the most important thing. Extensive study by the National Parks Service indicates that changes to windows should be based on other factors than energy savings. Collecting field-measured savings from numerous projects over the past decades, Michael Blasnik finds that "payback" for window replacement is in the range of 90 years. Beyond two-pane glass and basic tightening, window upgrades have little impact on energy use.
Fourth, low- and no-cost measures can make a big difference. Short of major changes to the efficiency of buildings, these measures have been shown to provide about 10% energy use reduction. Perhaps more important, 90% of Americans do not identify themselves as "confident do-it-yourselfers," perhaps placing the potential for low- and no-cost savings in the range of 1% of residential energy use.
Fifth, energy use reduction is pursued either for utility savings or to be more environmentally responsible. There are many reasons to pursue efficiency – many beyond utility bill savings and taking responsibility for the planet. In reality, one cannot avoid helping the planet if one reduces energy use. One can likewise not avoid reducing energy use if efficiency is pursued to help the planet. Moreover, all positive outcomes of reduced energy use are received, regardless of which one positive outcome a person names as motivating their energy use reduction. Incidentally, in most houses we audit, we believe that air seal work can be done in a way that will reduce fire spread hazard. Learning about potential fire spread hazard and how to correct it is by far the greatest positive outcome we believe the homeowner may receive from a knowledgeable energy auditor.
Tell us a little about energy audits. Why are they important? What should homeowners expect? How can they prepare for one?
Most clients say that their perceptions of the more important problems in their residences were entirely different after being shown by an auditor. Likewise, information about what to do about a problem that is provided by an audit is also often far different than what clients believed. Homeowners should expect to have a reliable, thorough, and well-understood game plan coming from their audit. The more our audit clients know about their building, their metered energy use, and their energy efficiency, the more they will get from the audit. At the same time, it is important that homeowners now expect to become experts in all aspects of managing the efficiency upgrade of their property. It is the energy auditor's role to provide expert assistance.
In your experience, what are homeowners always the most surprised to learn from their energy audit results?
Some improvements have 100 times greater bang for the buck than others. Costly improvements, and some that are highly advertised, may not match the energy waste we observe during our audit. When the correction that a client has heard so much about does not match observed problems, the correction may have far lower economic merit and appear far lower on a priority list than advertisements imply.
Are there any specific energy efficiency challenges that homeowners in your state or region face?
A difficulty we often encounter is that homeowners expect that insulation and heating installers are knowledgeable about efficiency, primarily because this is part of their training. Clients are surprised to learn that, until very recently, there was no training available locally about how to effectively and safely insulate a building or increase heating equipment performance.
What advice would you give a homeowner who is hesitant to schedule an energy audit because they fear the recommended improvements will be too expensive?
Check the package. Efficiency improvements are available for insulation, air tightening, windows and doors, equipment, ventilation, lighting, and appliances. Everyone needs an overall game plan. From among the 20 to 40 "plays" in a typical game plan, it's easy to pick one or two that you can do immediately.
In that same vein, what's one low-cost weekend project that homeowners can do to make their homes more energy efficient?
Most residences receive 10% of heating free of charge from south-facing windows. Often, south-facing rooms overheat though the thermostat may call for heating other areas. A fan, even the box fan most people already have, set to operate when south rooms get too hot may boost free passive solar heating another five to ten percent.
Now it's time for some inspiration. Tell us about one of the best home success stories you've seen in your time in this field.
We often follow-up audits with assistance during the installation phase. We're the owner's guide, not their contractor. By carefully managing insulation work so that it addresses air tightness defects, we have attained more than 50% air leakage reduction. This benefit accompanies the reduction in heat conduction that the insulation provides.