Can Increasing Energy Performance Be a Key to Unlocking Rural Home Affordability?

Abstract

Though home energy use should be considered in every residential project, it is particularly critical for low-wealth individuals and families. While higher-budget projects can rely on a return on investment for energy-saving features, “affordable” housing projects built by not-for-profit organizations frequently rely on reductions in construction costs to keep purchasing prices low for homeowners. However, this can result in higher maintenance and operations costs over the useful life of the home. Could linking home performance to the mortgage carry of an individual homeowner provide opportunities to create a housing stock of homes that consider the total cost of homeownership? This paper describes a research initiative designed to seek the balance point between up-front investments in improved energy performance and home affordability in support of a pilot, systems-based approach to more affordable homeownership. In a design-build studio format, the authors and their students have revised and constructed multiple versions of the same small, two-bedroom prototype home developed for the context of a mixed-humid climate: one built to the Passive House Institute U.S. (PHIUS) standard and the other to the Department of Energy’s Zero Energy Ready Home (ZERH) standard. By constructing two prototype homes on the same street and with similar orientation, but with differing energy-related details, the authors are able to evaluate the initial cost of construction associated with achieving these two performance standards while simultaneously comparing the monthly energy savings afforded by each approach. Each home underwent a rigorous process of modeling, testing, and monitoring. Computational energy modeling during the design phase were used to to test various envelope assemblies. At key points in construction, blower door tests and thermal imaging were utilized to assess the specific efficacy of alternative approaches construction detailing and to verify systems and envelope airtightness. Long-term monitoring is used to evaluate actual post-occupancy energy use against that which was predicted in the initial design phase. Furthermore, post-occupancy engagement with the homeowner allows for a deeper understanding of the design of end-user education programs that empower families to leverage the high-performance potential of their homes. Ultimately, these findings provide an invaluable contribution to the authors’ broader research and development where, in partnership with federal agencies as well as mortgage and insurance providers, the team continues to explore mechanisms to better integrate both the policies and products necessary to support a new paradigm of truly affordable homeownership to families in the rural South.