Luxury Sauna Experience: Maruni Woodworking and ONE SAUNA Collaborate

A groundbreaking collaboration between Maruni Woodworking Co., based in Hiroshima, and Libertyship Co. of Miyazaki, known for its sauna brand ONE SAUNA, has led to the development of the world's first furniture-quality sauna named kupu sauna. This innovative sauna is set to debut at the luxurious retreat Yuno-yama Sosuikyo, managed by Aqua Ignis Co. in Tokyo, marking a significant milestone in sauna experiences.

Unique Sauna Experience

The kupu sauna will be featured in two distinct rooms inspired by natural materials: the “Kino-toki” room, themed around wood, and the “Seki-rou” room, themed around stone. The design and functionality of these saunas are meticulously crafted to offer contrasting experiences aligned with the themes of these guest rooms.

A press tour and experiential event are scheduled for July 2, 2026, at Yuno-yama Sosuikyo, where attendees can enjoy guided tours and exclusive sauna experiences ahead of its grand opening.

Craftsmanship and Design

Founded in 1928, Maruni Woodworking has been celebrated for its exceptional craftsmanship, producing beloved designs for architects and artisans globally. The synergy between Maruni, the talented product designer Wataru Kumano, and ONE SAUNA brings together an impressive array of expertise to produce unparalleled sauna experiences. The kupu sauna features a unique half-dome structure that ensures steam circulates gently, providing a soothing touch as it envelops the sauna-goers, thus ensuring an unparalleled sensory experience.

Customized Sauna Experience

Yuno-yama Sosuikyo offers twelve luxurious independent villas, each themed with the beauty of natural materials, and is celebrated for its fully natural hot spring and exquisite dining. The integration of kupu sauna in the Kino-toki and Seki-rou rooms allows guests to experience saunas attuned to their specific thematic environments:

Features of the Kino-toki Room

- A pathway that leads through a wooden deck into the sauna area.
- kupu sauna chairs designed by Maruni for optimal comfort and relaxation.

Features of the Seki-rou Room

- A stone bath area complements the sauna, offering a full relaxation experience with cold water, followed by exposure to outside air.
- Similarly equipped with the kupu sauna chairs for ideal comfort.

Commitment to Sustainability

ONE SAUNA emphasizes the importance of local resources by focusing on eco-friendly sauna manufacturing practices. Utilizing Yoshino cedar sourced from Nara, known for its gentle texture and optimal heat retention properties, the kupu sauna showcases sustainable design while maintaining high standards of comfort. Recognized with the Good Design Award in 2020, ONE SAUNA continues to innovate in creating unique sauna experiences.

Furthermore, the kupu sauna incorporates a patented IoT management system, which optimizes energy efficiency through automated preheating that ensures the sauna is always at the ideal temperature upon guest arrival. This system also enhances safety by automatically cutting off the heater and notifying management in emergencies, underscoring a commitment to user safety and comfort.

Press Event Invitation

Join us on July 2, 2026, from 11:00 AM to 2:30 PM for a special media event at Aqua Ignis's Yuno-yama Sosuikyo, located at 4842-1 Komono, Mie Prefecture. Attendees will have the opportunity to enjoy a guided introduction, ask questions, partake in photo opportunities, and experience the kupu sauna firsthand.

Agenda:

- 11:00 AM: Opening remarks and Q&A.
- 11:30 AM: Room tours and facility photography.
- 12:30 PM: Sauna experience sessions by gender.
- 14:30 PM: Conclusion of the event.

This collaboration symbolizes a remarkable fusion of tradition and modernity, setting the stage for an extraordinary sauna era. Discover the unmatched quality of kupu sauna and immerse yourself in a unique relaxation experience.

For more details, please visit Maruni Woodworking and ONE SAUNA.