The purpose of this study is to reveal the characteristics of Kan as a compositional unit in relation with its usage, building base, structural system, and roofing system in Seo Baek Dang and Gwan Ga Jeong. The results are as follows： Seo Baek Dang and Gwan Ga Jeong share a common characteristics： Kan module forms the plan to be 1：1 in shape and enables flexibility in usage and regularity in compositional aspect. In Seo Baek Dang, there are active level differences in base, room floor levels and column heights to achieve intended roof design while minimizing the deviation of module (500 mm) of four sides enclosing the an-madang (inner courtyard) and, in Gwan Ga Jeong, instead of differentiating levels, maximizing the module control (up to 1,560 mm) and lowering the roof slope are found. They are regarded resulting in a rather plane manner. Through a comparative analysis, it is found out that these two houses have a common characteristics of Kan to form a quadrate plan while they have differences both in conceptual and tectonic manner that is 'how to build a house' in similar conditions of region, period and society. In addition, Kan as a module is clarified to have a relative value that regulates both structural and aesthetical aspects.
