In green home technology, solar energy and renewables still get most of the buzz. But experts stress the importance of reducing energy in addition to producing it.
While the buzz around green homes often centers around solar energy, high-performance homes’ expert Craig Foley urges home owners interested in energy efficiency to “reduce before you produce.” In other words, the primary focus should first be on insulation, ventilation, and selecting right-sized mechanicals; once those solutions have been installed and tested, energy production features can be considered.
Foley was one of three speakers at the High-Performance Homes Workshop at the REALTORS® Conference & Expo in San Francisco; he was joined by Melisa Camp and John Shipman. All three have earned NAR’s GREEN designation and have further earned the Green REsource Council’s EverGreen Award in recent years. Together, they outlined the three characteristics of high-performance homes:
1. Insulation and Ventilation
To create a complete thermal envelope, Foley prescribes insulation with varied R-values at each construction level. An R-value measures insulation’s ability to resist heat. “We recommend using R10 under the slat, R20 in below-grade walls, R40 in above-grade walls, and R60 in the top of the building envelope,” he said.
Ventilation goes hand-in-hand with sealing the home’s envelope, and concerns about a home being “too tight” are unfounded if a home is properly constructed.
Using the analogy of the human respiratory system, Foley said, “We don’t poke all kinds of holes in bodies to help us breathe.” Just as we can trust our lungs to be a proper ventilation system for our bodies, so can we trust a thoughtfully constructed, well-insulated home to be energy-efficient and free of issues like moisture build-up.
The advantages of super-insulated homesinclude reduced energy costs, comfort due to reduced noise, pest prevention, and the ability to lower one’s environmental impact.
2. Select Right-Sized Mechanicals
The efficiency of the home’s envelope is dependent on right-sized, efficient equipment, said Shipman. These mechanicals include HVAC, water heating, appliances, and lighting.
Finding the most efficient HVAC option can be difficult because customization is the only way to reach peak performance. The result of right-sizing an HVAC system is that “you can walk from one larger room, into a smaller den or bedroom and not feel any difference of temperature in the air.”
3. Produce Energy with Solar
Once you’ve reduced energy consumption hrough insulation, ventilation, and right-sizing, Camp said, “It’s time to produce!” Solar energy is the most common form of renewable energy for residential homes. Solar panels can be added to existing properties, but they can generate even more energy when they are included in the design phase of a house.
“Orientation affects home performance,” Camp stressed, so it’s best to orient a home to take full advantage of the sun when planning for solar PV technology. In most climates, Camp says a south or west orientation is best.
Copyright 2019 “Building a Green Home? Focus on Reducing Energy First” NATIONAL ASSOCIATION OF REALTORS®. All rights reserved. Reprinted with permission. August 21, 202November 14, 2019, https://magazine.realtor/home-and-design/feature/article/2019/11/building-a-green-home-focus-on-reducing-energy-first