Related story: Modulorbeat creates One Man Sauna inside a stacked concrete towerThe site is ranked by National Geographic as being one of the best places in the world to appreciate the sunset. The warm-toned woodwork swells into deep windowsills, and a hollow by a small side window forms an additional seating nook. Double and triple glazed window panes help to keep the heat in, while an insulating layer of aluminium foil behind the wooden panelling creates a tightly-sealed space to avoid draughts as the timbers expand and contract. Behind the burnt-timber exterior of this sauna by Canadian studio Partisans is a cavernous cedar interior that emulates the form of a seaside grotto (+ slideshow). Cedar wood was selected for its aroma, warm colouring, local origins and resistance to rot. «Creating the illusion of a carved interior, we formed the specially selected cedar timber into panels with parallel grains,» said the architects. Sans Souci Island, a lump of prehistorical granite that rises out of the water, forms the foundations for the wooden structure. The team used a Leica 3D scanner to study the rock formation and worked through a number of CNC-cut models before settling on the final design for the sauna. Slits in the tiered seating allow air to ventilate through vents and fans in the cavity between interior and exterior formwork. «As a cascading granite cliff shaped by glaciers into a peninsula, the rock offered both new possibilities and an unobstructed view of the horizon,» said the architects. «The selected concept for the Grotto prescribed a solid, simple presence on the exterior, while the interior followed dynamic air movements in curvature forms,» said the architects. The design is based on the natural formation of waterside grottos, which feature underground chambers carved and smoothed by the ebb of the water currents. «The result is a sculpted space, a sensual experience, and a sophisticated exercise in building science.»
The designers lined the space with curved wooden panelling, creating an undulating interior terrain encompassing a traditional stepped sauna seating arrangement and skewed porthole windows. A grate in the wooden surround airs the coals and encourages the heat to circulate.