Similarly, installing a smart or programmable thermostat might save homeowners between 10 and 15 percent on their heating and cooling bills. But these energy efficiency savings require correct usage of the technology! Millions of homes in North America purchase smart thermostats every year. Learning how to use smart home technologies is essential for increasing the operational efficiency of the structures we inhabit.

For this reason, the most rigorous and exacting sustainable building certifications, such as the Living Building Challenge, don't simply offer certifications to homes with the right technologies in place. Instead, they require at least 12 months of homeowner occupancy data. This requirement ensures that the humans who inhabit these homes know how to correctly use the sustainable technologies that builders and designers put in place during construction.

In an interview with Allison Capen, the former Technical Director of the Living Building Challenge, she told us that requiring a twelve-month performance period after occupancy enables Living Building Challenge project teams to know they have met the requirements. She went on to say that they learn along the way about reducing energy demand, commissioning systems, procurement policies, and educating occupants. Doing all this enables them to continue to operate as desired, even after the auditor is gone. The US Green Building Council also recognized the importance of ongoing operations and maintenance of commercial buildings when it introduced the LEED rating system for Existing Buildings. This rating system also requires at least 12 months of energy, water, and waste data to measure ongoing performance.

Why Does This Matter?

Over 70 million single-family detached homes in the United States use a lot of energy and water. A report by the National Academies of Sciences, Engineering, and Medicine stated that back in 1993, space heating and cooling accounted for approximately 58% of the total residential energy use in the US. They went on to say that, By 2011, heating and cooling made up only 48%, due to more efficient equipment, better insulation, and shifts in population to warmer climes. The study also found that overall home energy consumption increased during the same period. This increase was primarily due to a marked increase in the demand stemming from appliances, electronics, and lighting, in addition to the rise in the average size of single-family homes.

This report shows two exciting trends in household energy usage. On the one hand, home technology, including lighting, appliances, and mechanical heating and cooling systems, is becoming increasingly energy-efficient. Government programs like ENERGY STAR and WaterSense make it easy for homeowners to choose appliances and fixtures for their homes that consume less energy and water. On the other hand, and despite these energy efficiency gains, the total energy we use at home continues to rise.

At the same time, there is a massive potential for energy savings in the residential sector. A study conducted by the  Oak Ridge National Laboratory found that existing homes present a vast, mostly untapped potential for energy savings. The study states that by 2020, Americans could save about 3.25 of the 99.5 quads of energy in the US through residential building energy savings. They estimated that if the approximately 130 million single-family homes in America reduced their energy use by 40%, about 160 million metric tons of CO2 emissions could be prevented.

Per capita, household water use has shown a steady decline over the years due to improved technologies such as low-flow showerheads and dual-flush toilets. In 1970, 370 billion gallons of water were required per day in the United States or about 1,800 gallons per capita per day. That number has dropped to about 322 billion gallons—a 13 percent decline. The EPA estimates that the average American uses around 82 gallons of water a day per person for residential use. These results show that residential consumption is at least in part responsible for this drop in total water demand, despite a rapidly growing population.

This article offers a few important suggestions for how homeowners can adopt a new mindset to maximize their homes' sustainability.

This is not meant to be a harsh commentary on the human condition. Instead, we hope that it sparks ideas and conversations about how we think about sustainability—and how we might rethink our behaviors—in the world we live in today.