Following a long period of pause, construction on the world’s tallest building has officially resumed in Saudi Arabia. Beating the UAE’s Burj Khalifa by about 172 meters, the Jeddah Tower will span over 1,000 meters high and 1.5 square kilometers in its first phase of growth. This project is described as the ‘centerpiece’ of the Jeddah Economic City (JEC) development, intended to revive Jeddah’s urban core. Chicago-based practice Adrian Smith + Gordon Gill (AS + GG) Architecture led the design, envisioning a slender form conceptually derived from the fronds of a native flower emerging from the arid desert sand. The mixed-use tower will accommodate a Four Season hotel, apartments, office space, luxury condominiums and the world’s highest observatory overlooking the adjacent Red Sea. An overall cost of $20 billion USD is estimated for the project, with approximately $1.2 billion USD assigned solely for the tower. Read designboom’s previous coverage of the tower here
saudi arabia resumes construction on world's tallest building, jeddah tower
construction progress | image by Ammar Shaker, CC BY-SA 4.0, via Wikimedia Commons (cropped)
As reported on September 13, 20203, by the Middle East Business Intelligence (MEED), a local company known as Saudi Binladin Group (SBG) initially joined the Jeddar Tower project as the leading contractor, working closely with the German firm Bauer to complete the foundations and piling works back in the early 2010s. The latest report by MEE confirms that SGB has stepped down as a contractor. Still, the AS + GG team remains onboard as the lead architecture firm, teaming up with Lebanese company Dar al-Handasah joined in as an engineering consultant. Jeddah Economic City (JEC) has issued a tender for contractors to bid on the contract to complete the over 1,000 meter-high Jeddah Tower. The deadline for bids is the end of this year.
With the piling and foundational works already completed (constituting 1/3 of the building progress), on-site images currently reveal that construction of the super-structure in Saudi Arabia has reached level 50 out of of 157. The initial completion period was estimated at five years; the team has still yet to confirm the new numbers. 
saudi arabia resumes construction on world's tallest building, jeddah tower
the tower will span 1,000+ meters | image by S.Nitzold, CC BY-SA 4.0, via Wikimedia Commons
As construction progresses for the Jeddah Economic City project, the tower’s sleek structural form will gradually emerge, boasting a synergy between the technological and the organic. Its three-petal footprint optimizes residential space, while its tapering wings create an aerodynamic shape that reduces wind loading. The result is an elegant, cost-efficient, and highly constructible design that is both grounded in tradition and forward-looking, incorporating innovative thinking about technology, building materials, life-cycle considerations, and energy conservation. The tower’s elevator system will be one of the most sophisticated in the world, with elevators traveling up to ten meters per second. At level 157, a sky terrace will be open to the public and will be the world’s highest observatory.
‘While the design is contextual to Saudi Arabia, it also represents an evolution and a refinement of an architectural continuum of skyscraper design. Jeddah Tower’s design embraces its architectural pedigree, taking full advantage of the proven design strategies and technological strategies of its lineage, refining, and advancing them to achieve new heights,’ stated Adrian Smith + Gordon Gill (AS + GG) Architecture. 

saudi arabia resumes construction on world's tallest building, jeddah tower
render © Adrian Smith + Gordon Gill Architecture
saudi arabia resumes construction on world's tallest building, jeddah tower
render © Adrian Smith + Gordon Gill Architecture
render © Adrian Smith + Gordon Gill Architecture 

project info:
name: Jeddah Tower | @jeddahtower 
location: Jeddah, Saudi Arabia
architecture studio: Adrian Smith + Gordon Gill Architecture | @asggarch
development: Jeddah Economic City 
engineering consultant: Dar al-Handasah 
tower height: over 1,000 meters
phase one area: 1.5 square kilometers
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