LDA-140 Green Building Design
Emma Mallonee & Vincent Ray
Acros Fukuoka Overview
Thought-provoking, unique, and practical is just a few words to describe the Asian Crossroad Over the Sea, or ACROS, building in Fukuoka- a culturally rich and economic powerhouse in Southern Japan. Finalized in 1995, this structure has been a key element to retaining a sense of green space in the heart of a productive city, providing citizens with a touch of nature within the urban landscape (Greenroofs, 2020). Resting on the western side of the island, Fukuoka has a consistent subtropical climate with a spectrum from humidity to desert-like heat. Although temperatures there can reach nearly 100 degrees Fahrenheit in the summer, a rainy season the locals call Tsuyu occurs where the city can receive up to an average of 63 inches of precipitation (Metroblue, 2020). With these climate extremes, architects Emilio Ambasz and Nihon Sekkei have made a contemporary building that not only showcases the surrounding geography, but also can withstand harsh summers and wet winters.
CONTEXT OF DESIGN
The ACROS Fukuoka Prefectural International Hall sits on the southern banks of the Naka river, a geological break through the city which is dominated mostly by urban landscape. In 2018, the city of Fukuoka had 185 high rises buildings, 103 low rises buildings, and 14 skyscrapers- which all parallel smart-growth development (Emporis, 2020). Transportation, too, has to transformed the civil engineering platform with four mass transit options: the Fukuoka City Subway, the Fukuoka Airport, the J.R. Kyusyu Railroad Company, and the Nishi-Nippon Railroad Company- which offers both bus and rail transit options. These options are essential to the development of Fukuoka because there were reportedly roughly 488.3 cars to 1,000 people in 2013 (City of Fukuoka, 2020). The conservation of green space is essential to the livelihood of Fukuoka’s older population, where nearly 67% of the population is over 20 years old, in order to provide a space for meditation, exercise, and social gatherings.
A unique solution to a largely populated city, the 1,049,406 square foot building offers a multi-use space with room for concerts, offices, shopping, exhibition hall, and even an expansive underground garage for storage and parking. As one stands in the ago-urban design, the experience is meant to resurrect the aspect of natural features back into the cityscape. The most visually striking and exiting feature of the ACROS building is the fourteen ludicrously lush garden terraces, as well as a slick modern frame, allows this structure executes the balance of virgin versus developed property. The diverse climate had rendered Ambasz and Sekkei to construct this building on a northwest-southeast direction, this made sure that the sunlight and rain would provide both shelter and nourishment to the terraced-garden.
The mission of creating this useful, provocative building was to ensure that the community receives the open space it needs to take a step out of a city, and onto a lively, mountain-like feature which quickly removes you from Fukuoka’s financial district. The sustainable aspects of this construct allows for many energy-reducing practices such as limiting the heat intake and creating a cooling ventilation system, all without an HVAC unit with reducing the heat island effect as a product. Another demonstration of sustainability is the fact that the gardens act as a rain collection system, which is an amazing feature to utilize the intense winter storms, or the Tsuyu. While energy and environmental conditions taken into consideration, a long-term sustainable goal for this building was to reintroduce wildlife and native species of plants into the heart of the city of Fukuoka- creating a true bridge between nature and nurture.
UNIQUE ARCHITECTURE
ACROS Fukuoka Prefectural International Hall is a multiuse structure that offers entertainment and recreational space, including municipality offices, restaurants, a concert hall, and an area for art exhibitions. However, the purpose and design of the ACROS building proves to be more than just a part of the built environment- it is a structure that connects a bustling downtown financial district to green space. This building takes a thoughtful approach in finding a solution to lack of green space within the city by utilizing green roof material and technology, where the architect Emilio Ambasz had created a fragmented fifteen-level terrace rooftop garden which provides a biosphere for over 120 varieties of vegetation and 50,000 individual plants to thrive in (Greenroofs, 2020). This rooftop garden has many benefits for the community to enjoy, however one of the most prominent aspect of the large-terraced garden is to help combat Fukuoka’s air pollution crisis, where the carbon dioxide which is released in the city is then locally absorbed by this building.
During this construction detail assignment, we decided to focus on what makes the ACROS Fukuoka Prefectural Hall a unique approach to architecture and design in large cities. The rooftop garden terrace is an aspect of building design which takes into consideration many factors such as climate change and access to green space. Starting from the different varieties of native plant and tree species is the soil and root system complex. The soil and root systems play a crucial role in the natural success of these plants, and soil concentration measurements must be made with regional precipitation and climate taken into consideration. Underneath the root and soil complex, lies the root barrier fabric. This fabric, mostly created out of reprocessed polypropylene, is important because it limits the growth of taller vegetation, such as trees, from becoming too tall, as well as to keep the rooftop garden structure intact, making sure that no roots block drainage systems or create structural damage (Green Roof Technology, 2020). One of the most essential pieces of the green roof is the drainage and percolation systems, made from hard plastics, which allow excess rainfall to channel water down into the remaining other gardens. The drainage medium that is utilized in the case of the ACROS building is composed of small rocks or pebbles, and the reason that this material is used to ensure debris does not interfere with the channeling of water, as well as to ensure that the rooftop garden is properly aerated so enough oxygen can be received by the root system. Insulation, created out of the material cellulose and fiberglass, is added to the rooftop garden structure to retain heat and also encourage further airflow for the building below. The membrane protection and waterproof membrane, made primarily out of porous synthetic rubber and thermoplastics, are the last stages of the green roof, and that material is installed to allocate any remaining water out of the base of the garden into the drainage channel- this is designed to preserve and protect the concrete of the building’s exterior, as well as to prevent flooding and retain the concrete’s integrity (Kapsalaki, 2017). The fifteen-terraced rooftop garden contributes greatly to the performance of the building with regards to design, aesthetics, recreation, and helps combat local and regional air pollution. While seeking distance from the busy city streets below, this multipurpose structure is unique in appearance and practical in design.
METHODS:
Benefiting Biodiversity: With a planting medium of 12–24” deep Acros Fukuoka hosts over 120 species of plants now flourishing here from the original 76 that they had started with with seeds being brought in by birds and other small mammals highlighting how biodiversity finds refuge here benefiting the biodiversity of this area
This project has been featured in a magazine for its flood risk reduction abilities as this area receives heavy rainfall with it being a subtropical climate
Humid Subtropical Climate with an average rainfall of: 1665 mm | 65.6 inch and the rainiest seasons being: June, July, and August. Rain is collected through garden penetration, providing adequate water to sustain the vegetation all year round. The garden faces south in the northern hemisphere, providing ample sunlight to allow photosynthesis to occur.
This vertical greening her has resulted in a 15 degree celsius or 59 degree fahrenheit.
LAND USE PLANNING: Climate Mitigation
The architect found a creative solution via vertical greening that would provide a connection between the heavily-occupied downtown and allow for a space of refuge to exist within this influence of the surrounding landscape
ACROS has been accomplished at exemplifying adaptive measures to climate change within the built environment and become known as a success story in climate change adaptation
We can inspire green movements in cities, much like Acros has inspired a wave of urban greening across the city, aiding in the cities creation of the green curtain project that works with private and public citizens in the development of green infrastructure
LEARNED OPPORTUNITIES: Vertical Greening
Acros Fukuoka: Green roofs regulate buildings’ internal temperature and reduce building heating and cooling cost. Acts as an indirect stormwater management system to reduce runoff — can reduce stormwater peak flow rates by up to 65 percent and increase the time it takes the water to reach the sewer by 3 hours, lessening chances for urban flooding.
Water Conservation and Utilization of Renewable Resources: Cascading design of the building acts as a urban watershed, successfully providing vegetation on the ACROS with sufficient water
Opportunities for green enrichment lie around every corner of our city spaces, simple techniques of vertical greening, native plants, and utilization of the existing elements can aid in creating a self-sustaining design process.
CONCLUSION:
While we have learned alot in the process of analyzing the building effects on the surrounding enviornment and the effect it has had on the surrounding culture, there are also flaws present with this design in that it does not accommodate disbabled peoples which is a major flaw, with no lift options for garden available.
FLOW: must be present in the design process
While the plants aid in the sequestration of carbon dioxide, act as a cooling agent for the inside and surrounding building there are no renewable energy sources present.
- RENEWABLE ENERGY SOURCES: Must be present in design for sustainability
Life-cycle analysis of building materials had shown that the materials chosen, i.e concrete, have a poor life cycle analysis.
LIFE-CYCLE ANALYSIS OF MATERIALS: Need be employed to ensure future of materials recycling.
Being situated within the busiest financial district of the city of Fukuoka and simultaneously located adjacent to the city’s prized green space, Tenjin central park, the materials chosen for this project need reflect the serious side of business while depicting the softer green space. While I believe the materials chosen were to engage the observer in the multifaceted diverseness of use, I also believe that these were utilized to accommodate the nature of the many plants who dwell here, the ability for natural lighting, and for the longevity in the design. Whatsmore Japan is prone to having about 1,500 earthquakes per year, with concrete being a ‘natural disaster-proof’ (Dr. Ruggerio, Lecture), long lasting material the building will be sure to withstand many quakes to come. The transparency of glass makes its most eligible for this project, as the light may peak through and the outside world may observe from within. With the fragility of the glass and the solidness of concrete, together these two immerse themselves in a seamless flow.
Written and Edited by Vincent Ray and Emily Mallonee