The lavender exterior is made of a lightweight photocatalyst-treated ETFE membrane. (The Beijing National Aquatics Center, or "Water Cube," which was home to swimming events during the 2008 Summer Olympics, also has an exterior made of this material.) It absorbs solar energy and lowers dust levels, and it keeps a beautiful-as-new appearance even if it isn't often cleaned.
紫色外牆主要是塗上光觸媒的輕型結構薄膜（即 ETFE 膜材，2008 年京奧「水立方」國家游泳中心外牆亦採用這種膜材），具有吸收太陽能，降低灰塵附著的作用，即使不常刷洗，也可常保外觀美麗如新。