While transparency in general refers to the structure that is optically luminant or pleasant in its lightness, it is often synonymous with the concept of "modernistic." The advancement in construction and design technologies and the development of new materials with versatility adds even further diversity to transparency in architectural expression. The purpose of this study is to analyze various conceptions about transparency effects by comparing diverse expressions of visual lightness effects in space design. For this, I categorize and exemplify visual lightness effects of space applied to transparent materials. I argue that by utilizing transparent materials, the perception of space as well as boundaries between exterior and interior can be profoundly transformed. Space that overlaps through transparent boundaries creates atmosphere which deepens the architectural space environments.ironments.