Lotte Tower / KPF / Seoul

Lotte World Tower 

• Architects:  Kohn Pedersen Fox Associates, BAUM Architects
• Location:  Seoul, South Korea
• Client/Developer:  Lotte Property & Development
• Structural Engineer:  Leslie E. Robertson Associates. Chang Minwoo Structural Consultants, Thornton Tomasetti 
• Structural Material: Composite
• Project Dates:  2011-2017
• Architectural Height:  554.5 meter / 1,819 ft  
• Floors above ground:  123
• Floors below ground:  6
• No. of Elevators:  58
• Top speed of elevator:  10 m/s
• Tower GFA:  304,081 m2 / 3,273,101 ft2  
• Development GFA:  505,294 m2 / 5,438,939 ft2  
• No. of Hotel Rooms:  260
• MEP Engineer:  SYSKA Hennessy Group, WSP / Parsons Brinckerhoff 
• Main Contractor:  LOTTE Engineering & Construction
• Energy Consultant:  WSP / Parsons Brinckerhoff
• Facade Consultant:  ALT Limited, Lerch Bates
• Fire Consultant:  Aon Fire Protection Engineering  
• Vertical Transportation:  Fortune Shepler Consulting  
• Wind Consultant:  RWDI Group
• Elevator Consultant:  Otis Elevator Company, Mitsubishi Elevator & Escalator

The Lotte World Tower became the world's fifth tallest building upon completion in 2017, and is currently the only super-tall building (300 meters or higher) in Seoul. As it is located a fair distance from other tall buildings, the project's designers bore substantial responsibility to not only create an enduring skyline icon, but also to provide a culturally relevant and well integrated project within the urban grain. Beyond the spectacle of its sleek design and great height, the tower is part of a mixed-use complex that has provided additional public amenities. With its diverse program, it is hoped the project will become a beloved destination in Seoul.

The design of Lotte World Tower is both the product and an instigator of an urban paradigm shift - a restructuring of the commonly held beliefs that surround the nature of the urban environment. As the fifth tallest building in the world, Lotte World Tower has a responsibility to its occupants and neighbors. Rising to 555 meters, the tower's design takes the horizontality of the city and transforms it vertically, offering a range of programming while remaining thoroughly attentive to individual experience. The tower focuses on a vertical programming strategy that support efficient circulation, structural safety, and comfort. It offers a confluence of supportive system that creates an experience reflective of its height and stature. 

Lotte World Tower takes the horizontal life of a city and flips it on end. But this is not just an act of replication. The inversion delivers a new experience to the urban dweller, one that is expressed and felt vertically. The tower boasts 123 floors of mixed-use programming, designed with specific attention to the lives of the people within its walls. Retail, entertainment, and cultural programming provide a base for state-of-the-art offices, residences, and a luxury hotel, all topped with one of the most impressive observatories in the world.

Vertical Program - 

The programming strategy for Lotte World Tower is meant to be immersive and holistic. The vertical stacking increases the efficiency of the super-tall's programming, as well as its elevator layout. The podium provides a variety of retail, entertainment and cultural offerings, in addition to the public space found on floors above. Office space and amenities, including two floors dedicated to conference and event space, meeting and training areas, and cafeteria, are located on floors 11 to 39, while office-tel residences reach up to floor 75,. Floors 76 to 107 provide space for a luxury hotel with a landmark design and amenities for Seoul's guests. A publicly accessible, seven storey observatory caps the top of the tower providing incredible views of Seoul.

Efficiency in Movement - 

Circulation throughout a super-tall tower is an complex as in a dense horizontal urban environment, if not more so. Because experience is the number one design priority, efficient circulation strategies are of the utmost importance. Thorough analysis was required to offer the occupants of Lotte World Tower a premier experience. The goal was to fully eliminate any sense of artificiality that can be associated with ascending hundreds of meters within the confines of an elevator cab.

Structural Strategy -

Advanced capabilities in structural design push the limits of how tall we can build. Lotte World Tower was designed to withstand forces of nature that include hurricane-strength winds and earthquakes of a 9.0 magnitude on the Richter scale. Just as importantly, the tower's design reinforces a sense of comfort and safety to building occupants, even as they are enjoying the sights at the highest levels of the tower.

"The weight of the concrete in Lotte World Tower's foundation alone is almost seven times that of the entire Eiffel Tower."

Designing for Comfort in Windy Conditions -

The experience of a building at 498 meters - highest occupied floor at Lotte - is dramatically different from that of the ground floor. Wind can have a critical impact, both in terms of perceived stability and noise issues. Lotte World Tower's tapered shape is highly functional, its elegant from increases stability against wind load, assisting the tower in its ability to hold steady against an instantaneous wind velocity of 75 meters per second. Intensive wind tunnel tests were conducted by leading wind experts to ensure that the building could withstand local wind loads, both in terms of structure and cladding.

Evacuation Assurance -

Increasingly, a building's perceived safety relies heavily on the ability to quickly and efficiently evacuate in the event of an emergency. The striking heights of the worlds's super-tall towers mean that occupants must trust building operations to protect them in an emergency situation with efficient exit strategies. Advances in elevator technologies have not only made super-tall construction possible, but fulfill the expected standards of safety.

At the Top of the World -

A breathtaking experience awaits at the top of Lotte World Tower. Comprising the seven floors between levels 117 and 123, the observatory offers a completely panoramic view of Seoul and beyond. Including Incheon, Songdo and the Yellow Sea on a clear day. To reach the observatory, visitors are served by two double-decker express elevators, known as the "Sky Shuttle," which travels between basement and the observatory and can accommodate close to 900 people per hour, taking only one minute to reach the top of the world's fifth tallest building.

Conclusion -

As the world becomes increasingly denser, and buildings taller and taller, the human experience must remain at the forefront of architecture and design. Lotte World Tower is the product of a strategy for super-tall construction that caters to the individual experience, and provide a mediated transition from the ground plane, even as it stands as one of the tallest in the world.