Its regular size is 42.42cm, or 54.54cm for a big fireplace of the Urasenke school of tea ceremony, which is much smaller than common Irori fireplaces.
寸法も一尺四寸（42.42cm）あるいは裏千家の大炉の場合でも一尺八寸（54.54cm）四方で、一般的な囲炉裏よりはるかに小さい。