Experimental analysis of airtightness performance in high-rise residential buildings for improved code-compliant simulations

Abstract

Recently, the government of Korea announced a green remodeling policy to improve building energy efficiency and achieve the zero energy goals by 2030. As a result, the insulation performance of residential buildings has been enhanced every 2–3 years for the past 10 years. However, the airtightness performance has been revised once only for windows and doors. Also, energy modelers in practice still use a predetermined and fixed infiltration value for code-compliant energy simulations in the design stage without any differences in air leakages. Currently, a few articles investigated measured data of air leakage rates for high-rise residential buildings in Korea. Thus, typical code-compliant models may not represent realistic airtightness performances, especially in retrofits that were built in different construction years (i.e., the 1990s to 2010s). In this study, we performed the experimental analysis of the airtightness in residential buildings in Korea. The blower door tests were conducted in twelve representative households in the capital area. The results were compared to the previous measurement studies, and specific metrics were calculated to confirm the characteristics of influential factors on airtightness in residential units. The measurement showed that the airtight performance of the recently built residential buildings has improved by about 3–4 times compared to the residential buildings built 30 years ago. The identified airtightness in this study will provide better knowledge for designers and engineers to develop more accurate residential energy models for code compliance.