Spanish practice Estudio Herreros drew on architectural follies when designing a new floating sauna in Oslo, Norway, giving it a pitched roof and striking mint green exterior.

The Trosten Sauna is moored in the fjord next to the Munch Museum, which was also designed by the firm, led by Juan Herreros and Jens Richter, with offices in Madrid, New York City, and Mexico City. The mobile structure is the latest sauna commissioned by non-profit organisation, the Oslo Sauna Association, whose purpose is to bring ‘sauna to the people.’

‘We wish for everyone in Oslo to have access to high quality, hot saunas,’ says the organisation on its website.

Follies are usually found in parks and gardens and are typically ornamental, with no immediate use. Estudio Herreros has borrowed loose references for its sauna, giving it a sawtooth silhouette and mounting it on a floating concrete platform. The timber structure is clad in Hydro’s green aluminium panelling, made with 75% recycled aluminium, with terrazzo tiling and timber decking enclosed by steel balustrades.

Inside, it’s all about function and classic Nordic minimalism: Slatted timber is used for the ceilings, walls, doors, and stepped seating, with terrazzo tiling underfoot. A large glass pane offers views of the fjord, and the sauna can accommodate 24 people and two wheelchair users, while the external amphitheatre can hold 50.

The Trosten Sauna opened to the public last month. Visitors can book a session via the Oslo Sauna Association’s website.

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