YOKU is a modular sauna designed by marco williams fagioli (zup design). the inspiration behind its name is a particular branch of japanese natural medicine based on the beneficial effects of contact with plants and the woodland atmosphere. YOKU is an essential, well-balanced minimalist design that is also warm, welcoming and natural. the heater is built into the lowest bench thus displaying an uncluttered, linear effect. the large glass panel at the front features vertical elements in natural wood on the outside, which make the space inside more private and provide shelving that is open to the external environment. YOKU is available in three different types of wood: heat-treated aspen, heat-treated solid wood and canaletto walnut.