Constructed outdoor stage roof with transparent membrane material

(Tokyo Head Office: Setagaya-ku, Tokyo; Osaka Head Office: Yodogawa-ku, Osaka; President: Yumi Nomura), which handles large membrane surface structures (tent structures), civil engineering and logistics materials, was contracted to construct a membrane structure for the renovation of the “outdoor stage” at Tennogawa Park in Tsushima City, Aichi Prefecture (1 Miyagawa-cho, Tsushima City, Aichi Prefecture), and on July 14 The stage was reopened on July 14. For the stage roof, we used a highly transparent and lightweight ETFE film membrane, a material made of fluoroplastic rolled into film form. The stage roof using this membrane material is rare, and this is the first case of Taiyo Kogyo using this material.

The stage at Tenno-gawa Park has never had a roof, and many citizens have requested that the stage be made all-weather, usable even in the rain, for an even more relaxing park. The roof was designed by TONZAKO Design Inc. (headquartered in Nagoya City, Aichi Prefecture; Jun Matsuzaki, President), which designed the roof using a membrane. The city of Tsushima requested that the park be symbolically staged for the next era in commemoration of the 100th anniversary of the park, and Taiyo Kogyo was the first to use ETFE film membrane material for the roof of the stage.
In order to harmonize with the landscape of Tenno River Park, where much nature remains, ETFE film, which has high transparency and allows a variety of expressions, was used. In addition to the circular roof, which is reminiscent of the round pond in Tenno River Park, the structural design is reminiscent of the lightness of a lantern swinging on a straw boat by adopting the HP shell structure form. The new monument will be built as a new monument in the future. It is expected to remain in the memories of citizens and users as a new monument in the future.

ETFE film membrane material is a fluoropolymer rolled into film form and is attracting attention as a material that can replace glass for new architectural expression. In Japan, it is used for the roof of the new Toyosu Brillia running stadium and the facade of the former UNIQLO Shinsaibashi store (now closed). Overseas, it was used for the Khalifa International Stadium for the World Cup soccer tournament in Qatar, and is a membrane material that is attracting attention for its use in huge buildings.

(1) Durability
Despite its thickness of 0.5 mm, it has a durability of about 25 years, and since it has fire retardant performance, it can be used in Article 22 areas of the Building Standard Law, depending on the application.
(2) Transparency
It maintains high light transmittance (*86.8% visible light transmittance at 500 NJ (transparent, 500 μm)) in all UV, visible light, and infrared regions. Light transmitted can be controlled by using different film types (transparent, pear-shaped, white, blue, dot print, etc.).
(iii) Earthquake resistance
ETFE film (500 μm) weighs approximately 874 g/m2, which is lightweight compared to other common building materials. As with conventional membrane structures, it can significantly improve earthquake resistance by reducing the load on the building frame. It also has excellent deformation-following properties and does not break and shatter like glass, making interior spaces safer.

Tennogawa Park is a historic park that celebrated its 100th anniversary in 2020 and was selected as one of the “100 Historical Parks in Japan” in 2007. The park has a large lawn, a playground, and one of the largest wisteria trellises in Japan, which is the symbol of the park. The park is also the site of the Owari Tsushima Wisteria Festival and the Owari Tsushima Tenno Festival, which was registered as a UNESCO Intangible Cultural Heritage in 2008, and is loved by many tourists and citizens.
The Tennogawa Park Park-PFI (Publicly solicited Installation and Management) Project* was launched in FY2022, and Tennogawa Park Management, a business selected through a public solicitation process, has been developing the park’s facilities. The entire park was renovated with the aim of creating year-round liveliness through high-quality management and operation of the entire park and the implementation of events, etc., utilizing ideas, know-how, and funds from the private sector, including the opening of the Starbucks Coffee Tennogawa Park store.
In conjunction with the Park-PFI project, the outdoor stage has been completed with donations from group companies including Usami Oil Co.
The opening ceremony was held on Friday, July 14, 2023, and Mayor Kazuaki Hibi of Tsushima City cut the ribbon.

Tennogawa Park is an urban park with a history of over 100 years, designed by Shiguroku Honda, the “Father of Parks in Japan. Today is the day of the “One Grain, Ten Thousand Times Day” and the park has been reborn. Today is the day of the first ten-thousand-fold increase in the number of crops, and is positioned as the starting day for a great leap forward in achievement. We believe that this is the perfect day to celebrate a new beginning. It is thanks to all of you standing here, as well as many local residents and citizens, that we are able to celebrate the opening of Tenno River Park. I would like to conclude my speech by wishing that the wonderful Tenno River Park will become an oasis of rest and relaxation for all of you. Thank you very much.

What is the *Park-PFI (Publicly-Financed Installation and Management) Project?
This is a system to promote the development of urban parks by selecting private operators through public solicitation to establish and manage park facilities such as restaurants and stores (park facilities subject to public solicitation) as well as to develop park facilities (specified park facilities) in urban parks.

Location: 1-chome, Miyagawa-cho, Tsushima City, Aichi Prefecture
Client: Tsushima City
Designed by TONZAKO Design Inc.
Design cooperation: Kazuhide Doi Architects + H&A
Structure: Eishi Mitsuda + Jun Yanagimuro Structural Design
Construction: Daiwa Lease Co.
Membrane Structure：Taiyo Kogyo Co.
Supervision: TONZAKO Design Inc.
Start of construction: June 15, 2023
Completion: June 30, 2023
Scale: 22.9m x 21.6m x 12.7m (hyperbolic parabolic shell shape)
Area: 388.0 m2 (projected area), 417.0 m2 (surface area)

Taiyo Kogyo is a “leading company of membrane structures” that supports the safety and security of society. Under our corporate philosophy of “Unlocking the infinite possibilities of membranes to deliver an inspiring and comfortable environment to our customers. Under the corporate philosophy of “We will bring excitement and a comfortable environment to our customers by exploiting the infinite possibilities of membranes,” we are expanding our business into various fields, including construction, as symbolized by the roof of the giant dome, civil engineering, logistics, and environmental fields, by taking advantage of the characteristics of lightweight and strong materials. As we celebrate our 100th anniversary, we will further collaborate with our group companies in event and facility management, as well as strengthen our overseas business and research and development.

Official website: https://www.taiyokogyo.co.jp/

Press photos can be downloaded here.

Public Relations Department, Taiyo Kogyo Corporation Phone: 06-6306-3033
Mitsui (080-7077-0347)/Takaya (080-4017-4670)/Kagejima (090-2147-4572)