Simulation Analysis of Potential Energy Savings from Air Sealing Retrofits of US Commercial Buildings

The National Institute of Standards and Technology has demonstrated that, despite assumptions to the contrary, typical modern commercial building envelopes are not particularly airtight, resulting in significant energy costs. It also has been demonstrated that substantial energy savings could result through the installation of an effective air barrier in new commercial buildings. That work contributed to the consideration and adoption of air barrier requirements in a number of commercial building standards and codes (e.g., ANSI/ASHRAE/IES Standard 90.1-2013, ANSI/ASHRAE/IES/USGBC 189.1-2014, and International Energy Conservation Code 2012). Given that the existing building stock will continue to represent the majority of occupied building space far into the future and that the existing building stock tends to have leakier building envelopes, substantial energy and other benefits can be achieved if these buildings are retrofitted in a cost-effective manner. This paper summarizes the available measured data on reductions in U.S. commercial building air leakage through envelope air sealing and estimates the potential energy savings that could result for two commercial building prototypes. It applies a novel coupling of leading building energy and multizone airflow modeling tools using a new infiltration export tool.