Ondsauna Sauna by Taro Shimokawa is a highly esteemed winner of the very prestigious 2025 A' Design Award Gangsa in Arsitektur Competition Category.

GangsaArsitektur· 2025

Ondsauna Sauna

by Taro Shimokawa

Client: Ondpark

A' Design Award Gangsa Winner in Arsitektur Category

14,328
Verified Award Winner
Verify Award Status for #165443

View at A' Design Award Press Release Award Badge

Colors

The Design

About Ondsauna Sauna

Ondsauna adolah bangunan sauna nan dipasang di dalam rimbo. Dindiang lua nan tagak dikalompokkan disakitar ruang sauna, mancerminkan tumbuahnyo pohon ka ateh. Sabuah jalan spiral mananti ka ruang santai di atehnyo atok. Pintu masuak barado 250 milimeter di ateh permukaan tanah, dek pancaluran dingin (cold plunge) barado di 1000 milimeter, sarato di ateh atok barado di 3250 milimeter, sahinggo pagarakan dari sauna ka pancaluran dingin ka udaro tabuka bagarak sacaro vertikal. Rancangan lantai nan bapoligon irreguler sarato bangku-bangku basiku tumpul mangarahkan pandangan sarato mambuliahkan pangunjuang mamiliah tingkaik interaksi nan diinginkan.

The Recognition

About the A' Design Award Gangsa

Ondsauna Sauna adolah pamenang A' Design Award Gangsa, sabuah pangakuan nan sangaik bapresti nan dibarikan ka rancangan nan cemerlang nan dicirikan dek kreativitas, kacerdikan jo kabijaksanaan. Pamenang Gangsa adolah karya nan cukuik mahir jo kreatif sacaro mangesankan nan mamastikan pangalaman nan luas, imajinasi jo kacerdikan parancangnyo. Ondsauna Sauna dipaokan manjadi bando nan sangaik dihormati, dikagumi jo disayangi, nan profesional jo inovatif sacaro nampak. Rancangan nan manang Gangsa iko mamuek praktik tabaik dalam seni, ilimu, rancangan jo teknologi jo cemerlang dalam parhatian ka rincian. Ondsauna Sauna mamanuhi kaparluan jo elok, manyantuah karinduan, mamikaik parasaan jo manarik raso ingin tahu.

Behind the Design

Press Kit

Credits, team members and technical details provided by the designer.

Unique Properties: Trees grow endlessly upward, a concept reflected in the vertical exterior walls clustered around the sauna room. A spiraling path leads upward to a rooftop relaxation space, mirroring the building's form. The sauna entrance is at GL+250, the cold plunge deck at GL+1000, and the rooftop at GL+3250, so the transition from sauna to cold plunge to open air follows a vertical flow. Viewing the forest at treetop height allows one to share in its growth rhythm.
Dimensions & Packaging: The irregular plan was chosen to allow the passage and expansion of the line of sight and to adjust the degree of intimacy, which was rationally solved by the 150mm CLT floor slab. The elimination of beams has eliminated non-perpendicular joints in the structure, contributing to labor savings in site work. The rational walls of the scale module are discretely assembled and the CLT slab connects them. This structural form itself can be described as a sociopetal structure.
Production Technology: An irregular polygonal floor plan guides sightlines, creating varied scenic views. Research shows conversations are twice as frequent at 90 degrees versus side-by-side. Here, strangers sit together, so we chose obtuse-angled benches to balance interaction and privacy, encouraging conversation without intrusion. Varied seating allows for different levels of interaction, while the overall arrangement around a fire fosters a shared experience.
Inspiration: In a sauna, strangers sit nearly naked in close proximity, creating potential intimacy. Yet in Japan, public saunas haven’t fostered this sense of community. By aligning with Japan’s unique sense of closeness, we aim to create a sociopetal space, encouraging shared understanding without forced intimacy. “Non-intrusive” walls balance connection and separation; their verticality resonates with the forest, while their spacing draws nature in and modulates closeness among neighbors.

Read the Press Release