Energy efficiency matters to residential real estate stakeholders for any number of reasons. However, three reasons stand out. First, energy can be a significant contributor to the overall cost of housing, especially for low- and moderate-income households. Second, for housing providers, energy performance—or lack thereof—can influence a property’s value. And third, as climate change and pollution challenge the world, political and social pressures to reduce carbon emissions are mounting. On this last point, real estate is fundamental to reducing carbon emissions. According to the most recent data from the U.S. Energy Information Administration, residential and commercial buildings accounted for 40…