We will open up a new era for membrane structures with two themes: evaluation of ETFE structures and large-scale relocation construction.
Brillia Running Stadium
table of contents
- Encounter with membrane structure and the shock of Munich.
The charm of the membrane that led Kitamura to the ETFE structure. - Evaluation of construction period, cost, design, and legal reform.
The power that supports you every time you overcome a hurdle. - We use construction methods specialized for disassembly and reassembly.
The future of sustainable, removable architecture that takes advantage of the service life of building components. - It has received high praise and attention, including winning the Japan Structural Design Award.
ETFE structural evaluation has brought great progress to membrane structure architecture.
The Shin-Toyosu Brillia Running Stadium opened in Toyosu, Koto Ward, Tokyo in 2016 as a place where people who love sports, including citizen runners, people with disabilities, and top athletes, can share the joy of running together.
The stadium, which has been loved by many users for the past seven years, is currently being dismantled and relocated with the aim of moving it to the Ariake area.
Through the construction of the stadium, we used ETFE structures on a large scale for the first time in Japan, and we focused on two themes: receiving an evaluation for public notification, and designing for demolition and relocation without any on-site steel frame welding or membrane welding work. We spoke to Atsushi Kitamura (hereinafter referred to as Kitamura), who took on the challenge.
Jun Kitamura
Construction Business Headquarters Joined in 1996
Encounter with membrane structure and the shock of Munich.
The charm of the membrane that led Kitamura to the ETFE structure.
Kitamura, who currently holds the title of principal engineer at the construction business headquarters and
director of planning and research at the Japan Membrane Structures Association, can be said to be a standard-bearer for ETFE structures.
What was the process behind introducing the ETFE structure into the Shin-Toyosu Brillia Running Stadium, and what was your first encounter with membrane structure?
Kitamura:
Since my university days, I have been a member of the membrane structure laboratory in the Department of Architecture. When I was in high school and obsessed with baseball, Korakuen Stadium became the Tokyo Dome, and when I went to watch a game, I was drawn to the mysterious roof structure, which is what sparked my interest in membrane structures. After I started studying seriously, I was shocked by the Olympic Stadium in Munich, which was designed in 1972 by a famous engineer named Frei Otto. It has a unique shape and is of an amazing scale. Since April 2024, I have been serving as the chairperson of the Structural Design Subcommittee of the Architectural Institute of Japan’s Shell/Space Structure Steering Committee, and the committee has published the “World Structural Design Guidebook I” in 2019. I also wrote a book about this work. Similarly, we also wrote about the “New Toyosu Brillia Running Stadium” in the “Japanese Structural Design Guidebook” published in 2023.
I joined Taiyo Kogyo in 1996, and began researching ETFE structures at the company’s technology research laboratory in the early 2000s. When I first saw it, my impression was that it was highly transparent and the material was very thin. Honestly, is this okay? However, the more I learned about the material’s properties, the more I realized that it was an interesting material. The first time I was deeply involved was in the Japan Pavilion at the 2010 Shanghai Expo, an international exposition held in Shanghai, China. This roof has an ETFE structure, and I was in charge of its design. At that time, I was with Shinji Nanami and Ken Takai, who I worked with this time.
Conventional membrane structures have used white membranes, but the biggest advantage of the ETFE structure is that it can be made transparent. Because it allows ultraviolet rays to pass through, it is suitable for greenhouses and botanical gardens where plants are grown, as well as soccer stadiums that require growing natural grass. On the other hand, the disadvantage is that when sunlight enters and traps heat, the temperature rises too much. It is not always a good idea to make everything have an ETFE structure, but depending on the application and environment, it is better to use a white membrane in some cases. Additionally, the transmittance of ETFE can be adjusted by printing. Since we are a membrane structure company, we believe that this material has great potential, allowing us to choose from a wide range of materials depending on the application.
The ETFE structure that Kitamura saw had great potential.
In order to use the Shin-Toyosu Brillia Running Stadium as an opportunity
to amend the law so that this material can be introduced domestically.
Kitamura:
I think it was in 2015 that I first heard about the Shin-Toyosu Brillia Running Stadium. Initially, it was intended to be a training ground for Paralympians, and at a Toyosu meeting of local experts, a voice was expressed that Tokyo Gas wanted to make effective use of the land in preparation for the Tokyo Olympics. Ultimately, with the aim of creating a running facility where everyone can enjoy sports and art, plans were made for the facility, with Dai Tamesue, a former track and field athlete and three-time Olympic representative, serving as the director. .
The person originally entrusted with the design was Koji Takematsu of EPA Environmental Conversion Equipment. In 2005, Mr. Takematsu and Mr. Nanami of Taiyo Kogyo had built a temporary building using the ETFE structure, albeit on a small scale. It was done.
I started working as the main designer of the ETFE structure, and as I mentioned earlier, I have been researching the ETFE structure as a technology for about 20 years, and although there are many great achievements overseas, However, due to legal issues, it has not been possible to introduce it in Japan for a long time. In order to change the law, we need a track record, and the Shin-Toyosu Brillia Running Stadium could be the catalyst for that.
Evaluation of construction period, cost, design, and legal reform.
The power that supports you every time you overcome a hurdle.
Kitamura began the design process with a number of issues in mind.
With this construction as an opportunity, will ETFE structures be able to receive evaluations that will lead to legal revisions?
Kitamura speaks honestly about his feelings with a gentle smile.
Kitamura:
I had experience with several ETFE properties, including the Japan Pavilion at the Shanghai Expo, so I didn’t have to worry about being able to handle it technically. However, since the construction period was short, I was concerned that it would be a little difficult considering the amount of time it would take to receive evaluations in order to build a track record that would lead to legal revisions.
The other thing is the design aspect. Around this time, Zaha Hadid’s design was adopted for the new National Stadium, and there were plans to use an ETFE structure, but soon after Zaha’s plan was withdrawn, it was decided that the ETFE structure would be used on such a large scale. Since this was the first time the building had been built in Japan, we could predict that it would attract a lot of attention. In that case, the beauty of the design becomes more important, and it won’t be like building a warehouse or greenhouse. Since the membrane structure is finished as is, all the bones are visible, so based on the design of architect Takematsu, structural engineer Hideyuki Hagiuda of KAP Co., Ltd., and us PM The three members of Taiyo Kogyo, including Mr. Nanami, the site manager, Mr. Takai, and myself, thoroughly discussed the beauty that is unique to the ETFE structure. We thoroughly discussed everything from the frame type to the details of the connection with the wood, and the appearance of the ETFE air piping, and also conducted mock-up tests to reduce the slight wrinkles in the ETFE. I am truly grateful to all of you for working together with the same aspirations to create a design suitable for Japan’s first ETFE structural building, while keeping an eye on the construction period and cost.
Through the design and construction of the Shin-Toyosu Brillia Running Stadium,
Kitamura’s major responsibility was to receive an evaluation in order to have the ETFE structure registered.
The merits of receiving an evaluation are followed by an unexpected development.
Kitamura:
An advantage of having the ETFE structure evaluated is that if the track record is recognized, there is a higher possibility that the notification will be revised. Up until now, things that could be used after getting an evaluation are no longer being used because no one takes an evaluation, and the law has not changed, and in that sense, we are far behind compared to other countries. . Even if it is difficult this time, if it is evaluated and recognized as a track record, and the notification is revised, it will be possible to introduce it in the future without having to undergo evaluation, and the possibilities of the ETFE structure will expand greatly, so it is of great significance as a mission for the industry. It was something I wanted to accomplish somehow.
However, during the design process, an administrative decision was made that it was OK to proceed without receiving an evaluation. In other words, the ETFE structure is treated as a roofing material, not a membrane structure, so no evaluation is necessary.
Certainly, there is an advantage that the construction period will be faster if you do not receive an evaluation. If you look at the project alone, the advantage of the construction period is huge, and there was a time when I was almost swayed by that idea.
However, when I returned to the company and reported this, Takashi Nomura, then Managing Director, told me, “Don’t be so quick! If you receive an evaluation and become a track record, that will lead to a revision of the notification,” and he told me that the ETFE structure had to be revised. Legally, it is treated as a roofing material, but we decided to voluntarily receive BCJ evaluation from the Building Center of Japan, as it is equivalent to treating it as a membrane structure. “BCJ rating” is an evaluation of a building’s construction methods and components in light of building standards laws, etc., and the rating results are highly evaluated by administrative agencies as technical basis materials.
The design period took quite a long time, but after that, the project was recognized as an achievement, and the law was revised, so I am grateful for Mr. Nomura’s words. If I hadn’t said those words, I don’t think I would have won any of the awards that followed, so I think my current position would have been different. Although it was about 15 years behind Europe and other countries, ETFE has finally been established in Japan, and the legal system has created an environment where it can catch up with overseas countries.
When asked about Managing Director Nomura, who made the accusation, Kitamura mentioned the name of another employee along with his respect for Mr. Nomura.
The discussion also extends to Taiyo Kogyo’s flat corporate culture.
Kitamura:
Mr. Takashi Nomura is a pioneer and great senior in the field of membrane structures in general. For the past three years, I have also served as an employee of the Japan Membrane Structures Association, and Taku Nomura has been in charge of the association’s activities for a long time. He has been calling for the ETFE structure to be included in the law for over 20 years, so he has far more insight and commitment than I do.
We received support from another person, Keiji Mori, who was the sales manager for Kyushu at the time, in building a track record for ETFE structure evaluation. I was in charge of a property in Saga Prefecture called “Oshima Hospital Carriage Building” that used an ETFE structure, and the entrance canopy was only 70 square meters, so the government told me that I didn’t need to undergo an evaluation. He brought it to me because he thought it would be necessary to create a track record, and together we received an evaluation (performance evaluation + ministerial certification) as a track record. The results of these two cases were highly evaluated, and subsequent revisions to the notification were realized.
I don’t really have much contact with Mr. Nomura, who is my senior, but Mr. Mori is about two years my senior and currently serves as the manager of the China branch, and we keep in touch and eat together every time I go to Hiroshima. The fact that Mr. Mori is in-house responsible for Japan’s first ETFE roof at a new soccer stadium in Hiroshima probably has something to do with it. Sales staff from all over the country frequently ask me to come over for technical advice, including ETFE structures, and we continue to deepen our friendships after work. Lately, there have been an increase in the number of younger juniors, and I feel more reliable, but I hope that Taiyo Kogyo’s corporate culture of deepening friendships in a flexible manner will continue to be cherished.
Also, I want young people, not just sales people but also technical people, to actively go out and meet all kinds of people and expand their knowledge. I would like to work with young people in any way I can, such as providing technical and legal advice, as well as new challenges and new relationships. I want you to experience the excitement of wondering how you can do something, and the sense of accomplishment when you do it. If we only deal with products that have precedents and there is no evolution in membrane structure, the industry will inevitably shrink. We believe that membranes still have a lot of potential, so we interact with people who come up with new challenges for membranes, and as an organization we support those who stand on the front lines and bring their ideas back to the company. I believe it is important to have an internal system in place that can help make this a reality.
We use construction methods specialized for disassembly and reassembly.
The future of sustainable, removable architecture that takes advantage of the service life of building components.
With support from internal and external staff, construction of the new Toyosu Brillia Running Stadium continues with evaluation of the ETFE structure.
Next, we talked about another feature of removable architecture: its outline, benefits, and legal issues.
Kitamura:
The new Toyosu Brillia Running Stadium was built on the premise that after a certain period of use, it could be dismantled, transported to a new location, and reassembled. Therefore, we have completely eliminated the need for on-site steel frame welding and on-site membrane welding, and have designed the building so that it can be dismantled by simply removing bolts and other bolts. Initially, we had difficulty finding a new location, but we are very happy that TSP Taiyo, our group company, decided to move the facility to Ariake as a member of the company.
The biggest advantage of removable buildings is that there is no need to manufacture new components, which is superior in terms of construction time and cost. In the first place, building materials have a long lifespan, and ETFE structures can last for over 30 years, so it would be a waste to throw them away after about 7 years. After being used in Toyosu for seven years, it has been decided that it will be relocated to Ariake and operated for another 10 years, meeting the demands of a sustainable era.
The idea of using materials rather than throwing them away also applies to temporary construction. I previously worked on the structural design for a work called “Ark Nova.” Ark Nova was conceived by architect Arata Isozaki and European architect Anish Kapoor after the Great East Japan Earthquake in 2011, and was completed in 2013 under the design of Isozaki Aoki & Associates. It is an inflatable concert hall with a capacity of 600 people, and after use, it can be tightly folded and stored in a container. Since 2013, it has been used four times in different regions. This work was the one that moved me the most when it was completed, and I actually worked on it together with Mr. Nanami.
However, in the case of temporary buildings, current laws are limited to use for events or other purposes within one year, and if the building is to be used continuously for two to three years, the same laws and regulations as for permanent buildings are required. In that case, membrane structures are difficult to use for event purposes. If in the future, the law is revised in the short-term construction category and membrane structures such as ETFE can be used for event purposes, I think demand will increase even more.
It has received high praise and attention, including winning the Japan Structural Design Award.
ETFE structural evaluation has brought great progress to membrane structure architecture.
Japan’s first large-scale ETFE structure. The Shin-Toyosu Brillia Running Stadium is a removable building that uses a hybrid structure of curved laminated timber and steel arches.
It has received high praise from numerous domestic and international awards, including the 2017 Japan Structural Design Award, the Good Design Award, the 2018 BCS Award, the 2019 Architectural Institute of Japan Award (for works), and other overseas awards.
Kitamura:
The attention paid to the Shin-Toyosu Brillia Running Stadium has been higher than expected, and over the past seven years, a total of about 5,000 people have attended ETFE and this facility, including the approximately 2,000 people who gathered for the completion ceremony. I think I have explained. The subjects of our explanations range from design offices, general contractors, government officials and local governments to university laboratories and academic societies. In 2016, many people who came to Japan for the international association for shell and spatial structure (IASS) visited and gave explanations.
Perhaps because of that, the ETFE structure hasn’t really exploded, but its track record in Japan is steadily increasing, and there are many times more opportunities to explain it to customers during the planning stage. It was also used in a soccer stadium. Although it is difficult to simply use the term deregulation, I would like to continue our efforts to create a legal system and environment that can be used in a wide variety of places, not just ETFE. In 2024, the notification on membrane structures that I have been working on since I came to the association is expected to be revised, so the degree of freedom in designing membrane structures will increase even more, and the appeal of membrane structures that are lightweight, soft, and envelop the world will be enhanced. , I think we can reignite it in Japan.
Although there are not zero competitors, there is an advantage for other companies in that we can do things that they could not do before. Taiyo Kogyo has a large share of the market for membrane structure construction, and we also belong to the Japan Membrane Structure Association, so we hope to continue to expand the field of membrane structures and invigorate the industry as a whole. That’s what I think.