An old apartment unit in central Tokyo, measuring 37 square meters, was remodeled on a tight budget to provide increased light penetration, natural air circulation, and insulation. A genkan (entrance space) with ample storage was added. The bathroom space was expanded into the connective space at the center of the residence, with separate spaces for the bath, toilet, and sink. Several different types of transparencies (glass block, frosted glass, clear glass) were utilized to differentiate spaces through light penetration and privacy.