A system-level approach for designing multi-family sustainable and energy-efficient housing communities

This study introduces a system-level methodology for designing multi-family sustainable housing communities. This methodology is flexible and user-friendly, and can be implemented by both researchers and design practitioners. It can be applied in assessment of various energy efficiency measures and energy delivery options that can be considered during the early stages of design and development. The overall goal of such a system-level process is to provide a quick and efficient approach for identifying various design trade-offs early in the design process, which leads to an acceptable final design. The authors have utilized a sustainable housing community that is under development in Bloomington, IN, U.S. as the case study to illustrate this methodology in the design process. Ten building variables that were deemed to have a significant influence on energy consumption and/or construction cost were considered for potential inclusion in the final design. During the process, a baseline building model was carefully defined according to applicable energy standards, available reference building models in the U.S., and community and developer preferences. All energy saving measures are considered relative to this baseline building model. The results of a sensitivity analysis show that advanced energy delivery options (such as geothermal heat pumps, energy recovery ventilators and heat pump water heaters) can significantly reduce the Energy Use Intensity (EUI) of the building as compared with adjustments to the envelope. In the final scenario, more than 45% of the annual baseline energy consumption is reduced from the initial design.