Council on Tall Buildings and Urban Habitat
Mode Gakuen Spiral Towers, Nagoya-shi
Featured June 2014
Mode Gakuen Spiral Towers was recognized as a "Best Tall Building Asia & Australasia Finalist" in the 2009 CTBUH Awards Program.
Other Featured Tall Buildings

“Finally we see a rotated tower scheme that has real integrity. It is well planned and creatively varied in its spatial experiences.”
- Gordon Gill, CTBUH 2009 Awards Chair, Adrian Smith + Gordon Gill Architecture

Location
Nagoya-shi
Completion
2008
Height
170 m (558 ft)
Stories
38
Primary Use
Education / Office


Owner/Developer
MODE GAKUEN
Design Architect
Nikken Sekkei

Structural Engineer
Nikken Sekkei
MEP
Nikken Sekkei
Contractor
Obayashi Gumi Corporation

There have been numerous proposals for ever-elaborate, twisting towers in recent years, though few have come to fruition. The Spiral Towers stands in marked contrast to those hypothetical-only designs; a real, incredibly-spiraling form standing vibrant on the Nagoya skyline.

The considerable technical innovations made to achieve this—the structural, MEP and cladding solutions—are only part of the story. In a world of tall buildings dominated by office, residential and hotel functions, this building innovates radically with program, incorporating three educational-school facilities harmoniously into its twisting high rise form. The result is both a stunning skyscraper sculpture in the urban context externally and a series of unique and dynamic spaces internally. This building really does shine a beacon of light for those numerous twisting tower proposals yet to come to fruition around the world.

Figure 1. Tower withing the context of the city of Nagoya-shi

Mode Gakuen Spiral Towers is located on a busy main street of Nagoya City in front of Nagoya Station. The building houses three vocational schools; Mode-Gakuen for fashion, HAL for information technology and design, and ISEN for medicine and welfare.

The design of a spiral shaped building was created to reflect the strong vision of Masaru Tani, President of Mode Gakuen. It was thought that the unusual twisting shape would promote an environment for fostering creativity within the schools. Furthermore, the concept for the tower is derived from the enthusiasm of the students from the three schools, twisting and rising up into the sky, then soaring out into the real world.

Figure 2. Building entry
The Spiral Towers have become a new landmark for Nagoya City. The unique design of the three wings of the tower, twisted in helical form, appear to change shape when viewed from different angles, giving an elegant yet dynamic impression. In addition, a soft silhouette of the building resembling the bottom of a dress in 3-dimensional form brings the city  a rich image and a new face. A sunken garden was also created at the bottom of the building, to connect the underground and ground levels.
The Spiral Towers achieve high seismic capacity through a strong inner truss tube and two vibration damping systems that self-adjust and sway against the movement of the building according to its natural period; vibration-damping columns efficiently absorb seismic energy by means of viscosity dampers which are installed at 26 points on the periphery, and there is also a mass damper located on the rooftop. Quantitative analysis has confirmed that deformation during an earthquake is reduced by up to 20% compared with the non-inclusion of damping systems. 
Figure 3. Vibration control system

Double-glazed windows and air-flow windows are employed to reduce heat loads created by the sun around the perimeter zone. A District Heating System is tapped into for both heating and cooling, with the facility located on the near east  side of Nagoya Station. Even though the tower is spiral shaped, the structure allows the energy supply to be distributed efficiently and is enhanced through the use of strategically placed inner tubes located in the center core. This concept improves overall energy usage and upgradeability.

Figure 4. View looking up at tower’s twisting façade
Figure 5. Tower at night
In addition, high-efficiency lighting equipment, outdoor air cooling systems, and cooler fan rotation control have been applied for energy saving. For contribution to the community, a rainwater tank is located within an underground pit to reduce the impact of the sewerage system overspilling in torrential rains.

The design was planned to optimize the pedestrian network and spaces around the Nagoya Station area. As a result, the streets see a unified setback to the building walls, with vegetation planted and sidewalk areas widened. In addition, a café and retail stores are placed in front of the building to activate the ground plane, as an anticipated 8,000 students will commute to the school and thus enliven this area of the city.
Figure 6. Multi-purpose hall
While the twisting building form is not new to high-rise design, Spiral Towers presents a consistency and richness in its development both structurally and aesthetically. The form works beyond just the sculptural aspect when viewed on the skyline, and the programming of the space within the tower is carefully planned and organized such that the users are aware of this twisting form, even from within.

Related Links
CTBUH Skyscraper Center Profile:
Mode Gakuen Spiral Towers

Mode Gakuen Spiral Towers was recognized as a Best Tall Building Asia & Australasia Finalist in the 2009 CTBUH Awards Program.
Download Mode Gakuen Spiral Towers 2009 CTBUH Awards Book section

2009 CTBUH Awards Book

The CTBUH would like to thank Nikken Sekkei for their assistance with this article.
Photography © Nikken Sekkei