According to historical material (such as "Chanoyu Monjin") which was written when SEN no Sotan was alive, the Senke School (Sotan School) in those days fundamentally distinguished between the daisu in shoin tea room and the daisu in Sukiya (a four-and-a-half-mat tea room).
千宗旦の頃の史料（『茶湯聞塵』など）によると、当時の千家流（宗旦流）には基本的には書院の台子と数寄屋（四畳半）の台子という区別があったらしい。