Journal of Korean Institute of Architectural Sustainable Environment and Building Systems ISSN:1976-6483(Print) 2586-0666(Online) 한국건축친환경설비학회논문집

Since ECO2 program, a national certification program, is for certification, some algorithms were omitted so that the results do not differ significantly depending on the evaluator. Currently, the same program is used in remodeling, but a reliable program that differs little from actual energy use is needed during remodeling. Among the algorithms omitted from the program, the algorithm for the influence of unheated spaces was also omitted. As a result, heat transfer between adjacent zones was omitted, which may result in a difference from the actual building energy use. Therefore, this study analyzed the impact of unheated space temperature on building energy demand. The difference between reflecting and not reflecting the unheated space was compared, and various application methods for the temperature of the unheated space were reviewed. As a result of the analysis, it appears that there is a large difference in energy demand when applying and not applying the temperature of unheated spaces through a detailed calculation method, and when applying it through a simple calculation method. Accordingly, it is necessary to consider applying the temperature of unheated spaces through a detailed calculation method.