Abstract: Residential homes consume 24% of total primary energy while commercial buildings use an additional 19%, totaling 43% of all energy consumption in the U.S. (United States Energy Information Administration [USEIA], 2011). Wall assemblies are a fundamental component of a building's construction and can make significant impacts on building performance. Wall assemblies impact the environment, the builder, and the homeowner in various ways. Depending on the assembly method used to construct walls, a builder may find it easier or more difficult to install, and will identify a labor cost accordingly. Homeowners desire a wall with an affordable cost and appropriate thermal performance. Environmental concerns include using rare or readily available materials or avoiding use of materials which require more energy to produce than they offset. Exploring these factors to discover the ideal wall assembly is critical to enhancing building construction and performance. The purpose of this study was to identify optimal wall assemblies from the US Department of Energy Solar Decathlon 2011 using a newly developed Sustainable Cost Benefit Assessment (SCBA). The wall assemblies were analyzed using cost per square foot, clear wall R-value, and embodied energy metrics as a means for comparison. Reviewing the entries to the Solar Decathlon 2011 it is clear that the structures incorporate unique wall assemblies, which have not yet been studied. The results of this study provide data showing which of these wall types may prove to offer the most energy efficient, affordable, and environmentally conscious options. In addition, it contributes data to suggest which methods should not be adopted for widespread use. The conclusions of this study help supply valuable information describing which wall types are the best options for reducing building energy consumption.