Sign up for VMSPACE, Korea's best architecture online magazine.

Login Join

Data Center: New Architectural Typology Faced with Challenges and Limitations: The Architecture of Data Center GAK Sejong

written by
Ye Jungeun, Kim Sungyeol
photographed by
Jang Mi
materials provided by
NAVER Corporation, Junglim Architecture, Mass Stud
edited by
Bang Yukyung

SPACE December 2023 (No. 673) 


The existing landscape of the site (May 2020) 


[ESSAY] The Architecture of Data Center GAK Sejong ​


NAVER Corporation and Data Center

NAVER Data Center GAK Sejong (hereinafter GAK Sejong), the second data center of NAVER Corporation (hereinafter NAVER), is constructed with the hope of protecting our own things, and at the same time, providing new opportunities and milestones for the industry of the twenty-first century. If searches in a certain language do not produce valid results, it will hinder the utilisation of information and gradually weaken the influence of the language. People with their own language need a home-grown search engine in order to maintain their information competitiveness. NAVER’s data center is designed to accommodate NAVER’s unique search engine and to facilitate services provided by NAVER.

Data, known as the ‘oil of the twenty-first century’, is recognised as a future resource for national competition. As a result, data sovereignty – the right of countries and individuals to decide when, how, and for what purposes to use the data they generate, including questions of ownership – is also an important issue. The fundamental capability to develop and operate digital platforms is also part of a country’s data sovereignty. As technological competition enters its most intense phase on a global scale, users around the world, most of whom subscribe to online services provided by American companies, are now more aware of the danger of allowing the companies to monopolise data and revenue of related industries. Internet users around the world are paying growing attention to NAVER as a new service provider. In line with the change, NAVER creates sustainable services that help constitute our lives. For example, based on various service platform technologies, we connect businesses while studying and testing the lifestyles of the near future with artificial intelligence and robots. All records of such activities are stored in the servers, where they also serve as outstanding resources, helping to upgrade our services. NAVER’s data center will become an anchor data center for people in Korea and around the world, and act as a foundation for their daily lives.


The existing landscape of the site (May 2020) 


Second Data Center, GAK Sejong

The second data center, after NAVER Data Center GAK Chuncheon (hereinafter GAK Chuncheon), is planned with an increased size to store 20 years of data, with consideration for data usage. First, a competition was held for local governments to select one out of 110 proposed sites, which determined the current site on the outskirts of Sejong based on selection criteria such as capacity of electricity and water, complaint resolution, and cost. GAK Sejong, on a site of 90,000-pyeong (293,697m2), nearly six times the size of GAK Chuncheon, is a space that embodies NAVER’s philosophy, and the company’s architectural attitude. Based on the experiences of NAVER’s previous architectural projects (Green Factory, GAK Chuncheon, Connect One), we set three main goals for the project: sticking with the essence of the ‘gak (閣)’ that stores data, making space for functions, and giving top priority to ecological environment. Of course, the priority was to complete the building within the planned schedule and secure its stable operation, but at the same time, we first thought about how to make various entities coexist in the given environment. How can nature at the site, the servers in the data center, and the operators of the servers live together in harmony? In a situation where humans must intervene in nature due to the huge scale of the project, we decided that it was most important to protect the ecology of the site. On the other hand, we held a three-stage design competition from 2019 to 2020 to find the right collaborators who could effectively implement our goals and operating system. From the beginning of the competition, we made it clear that this was not just a design competition, but it focused on team building and technical proposals, and presented the main challenge of how to expand architecture through phased development. We provided three specific requirements in the design guidelines: the proposal of a modularisation system for the building, economic feasibility that was viable on various site conditions for future construction, and new technologies for electrical and mechanical equipment used in server rooms. However, it was disappointing that many proposals in the competition were technically untested and outdated.


(left) Construction of the site (January 2021) (right) On-site view of Sever Building (September 2022)


The Ecological Environment of GAK Sejong

The first task of the 2nDC TF, architecture task force for GAK Sejong, was to investigate the vegetation and land characteristics of the site. We documented everything from the trees to the grasses in the forest and investigated even the ground by soil analysis. The site is in a valley in the middle of a mountain, and we found a granite layer from 3 – 5m below ground level, and surface water flows on the bedrock along a waterway leading to the Geumgang River, which shows groundwater level is high. We also found several important waterways running through existing terraced farmland and the site. The construction on the slope would require extensive logging. We set the goal of preserving the waterways and forest trails, taking advantage of the topography if possible, and allowing the mountain to return to its natural state. Oaks, pines, chestnuts, willows, and a variety of perennial grasses were found on the site, and their records became important data for the environmental design with the aim of their restoration. We transplanted some of the willow and oak trees on the site and planted seeds of 20 different perennial grasses there. With winter just around the corner after summer and autumn, we can see that they settled in GAK Sejong in a healthy and beautiful way.


Master Plan, Technology, and Environment

The greatest challenge in the master plan design was how to locate GAK Sejong into the steep slope in the mountain. The operational organisation of the data center was required to meet difficult conditions such as ‘Don’t expose the building’ and ‘Connect all sectors with horizontal circulation.’ In order to minimise energy consumption for building maintenance in addition to energy consumption for server operation, we looked for conditions that would provide a stable building layout and secure uptime▼1 using natural wind. In this process, members from partners HDR, HanmiGlobal, and G. S. Engineering & Construction, who carried out data analysis of the natural environment, played a key role in placing the Server Building and electrical room in the safest and most secure locations.

The building’s mass gradually took shape as the size of the basic module and the layout of server room racks were determined. The entire mass began with the basic modules inside, which were optimised for user patterns to increase the usability of the space. The most important user in GAK Sejong is the server. We wanted to avoid design that prioritises sculptural beauty or aesthetics over function in a way that causes users to endure inconvenience. The core of the project was creating a responsive and protective space that helps building users – servers, people, and robots – fulfill their roles, while conserving the ecological environment.

(left) Lower part façade of Sever Building (October 2022) (right) Rooftop façade of Sever Building (January 2023)


​Materials of Data Center

While it can be awkward to use the term ‘environmentally-friendly’ in architecture, GAK Sejong focused on how to reduce contamination of its surrounding environment. In the construction area, we set the goal of using standardised prefabricated materials in all sections without waste (loss) and set the standard size of materials at 1,200 × 2,400mm. We established a guideline for the selection of materials based on the following conditions: minimally processed materials, materials that reveal their properties in cross-section, materials with least chemical treatment, materials with appropriate stiffness for the scale of the project, and sustainable materials. The collaboration with FRONT who participated in the façade design gave us confidence and assurance in our materials. To select building materials, we had to understand the entire system of production, processing, construction, and operation. Materials that require a lot of processing and moulding during production are bound to generate a lot of pollution and require a lot of operational resources for future maintenance. We decided that building materials that need to be intensively maintained can be a burden on data center operators and are inconsistent with the nature of data centers. We established a principle to prioritise recyclable or bio-degradable materials, and we tried to avoid using air-freighted stone or plastic moulded materials. However, we had a very limited choice in materials that met our requirements. 


Information Design

The information design process of GAK Sejong was much faster than other architectural projects. Architectural information design, commonly referred to as ‘signage design’, is usually ordered at the end of architectural design or at the time of interior design. However, due to the complex relationship between the space and its surrounding environment, and among the space users – humans and robots – this project started the signage design unusually early in collaboration with partners including CRAFIK and Junglim Architecture. As the architectural design and construction were being carried out in a complex manner with consideration for environment, human, robot, and server as a whole, the signage design had to be carefully planned and integrated into this process. After establishing the concept and visual motif of ‘connection and expansion’, anodised aluminum was selected as the uniform material in accordance with the policy of using minimally processed materials to harmonise with the overall concept of the project.


(left) Interior of Sever Building (November 2022) (right) Rooftop of Sever Building (December 2022)



The decision-making process behind GAK Sejong placed greater priority on safety and scheduling. Most of the intensive design during the design period was completed on schedule. During the construction period, we conducted various mock-up tests to validate design and organise construction details of architecture and civil engineering, proving the forms we had worked out together. Of course, we encountered various difficulties and obstacles during the collaboration process. We couldn’t continue the team building organised during the design competition, and we had to change members and even collaborating companies. In the process, the project was rushed to the point where we couldn’t afford to take care of each participant individually, and more and more issues needed to be solved at the same time. The creation of GAK Sejong was all done through the collaboration of many companies: ONE O ONE architects analysed the history of the site and formed the basis of master plan at the beginning of the project; HDR International proposed various technologies, though they were difficult to realise in Korea; Junglim Architecture steadily oversaw the entire project for a long time; FRONT was responsible for façade consulting and engineering design; MASS STUDIES designed staff accommodation and annex buildings. 

Above all, it was vitally important for the project to connect and restore the existing ecological environment, and the collaboration among experts in various fields helped successful completion of the project. These experts included Seo Ahn Total Landscape, which designed external environment, Beyond Landscape Design Group which carried out design development and construction documents, DAWON Landscape, which was in charge of construction, G. S. Engineering & Construction, which followed the requirement to maintain the original terrain on site, and HanmiGlobal, which managed the whole process consistently in one direction. As of November 2023, one-sixth of GAK Sejong has started up. The remaining five-sixths of the Server Building will start operating sequentially. We hope that various companies can create a better living platform by learning from the challenges we faced, and drawing upon our execution, record of failures, and open information when creating similar architectural environments. Furthermore, we hope that GAK Sejong will play a meaningful role as an intermediate process for the future of architecture, not limited to data centers.

(left) Rooftop of Staff Accommodation Building (January 2023) (right) On-site view of Staff Accommodation Building (March 2023)


1.  Natural wind is useful when it is around 24ºC and skies are clear. Air of higher or lower temperature requires additional energy to maintain the right temperature.

You can see more information on the SPACE No. December (2023).

Ye Jungeun
Ye Jungeun graduated from department of production design of Hongik University and then studied a graduate programme in architecture at Korea National University of Arts. She has directed NAVER Corporation’s architectural projects in NAVER Space TF from NAVER Green Factory in 2008, to NAVER Data Center GAK Chuncheon, and NAVER Connect One. She is currently working in Environment eXperience (EX) team at NAVER and was the executive director of architecture task force for NAVER Data Center GAK Sejong (2nDC TF) from 2019 to 2023.
Kim Sungyeol
Kim Sungyeol graduated from department of mass communication, college of communication at Hanyang University. He has worked at NAVER UX Team since 2016 and moved to EX Team, and he was the branding director of 2nDC TF from 2019 to 2023.