From Thriving Docklands to the British Capital's Business Hub

Canary Wharf, a 128-acre celebrated area of London, U.K., is an epitome of human creativity and resilience; constantly reinventing itself throughout centuries to mirror pivotal economic and cultural shifts in society.

The district's rich history dates back to the 1800s, when an empty marshland was transformed into thriving docklands to support London's status as the world's busiest port. In response to the changing business model of international shipping in the second half of the 20th century, the area underwent an inspired redevelopment with the introduction of Docklands Light Railway, London City Airport and the Jubilee Line underground extension. In the early 90s, the estate embarks on yet another visionary transformation, becoming one of the most important commercial and business districts in the world; by 2020, 16.5 million square feet of iconic office and retail space is built to accommodate an impressive daily professional population of over 120,000. 

Canary Wharf continues to evolve and in the midst of a progressive metamorphosis into a mixed-use urban destination, offers both residential and commercial real estate, a diverse selection of cafes, bars and restaurants, one of the largest roof gardens within London, an acclaimed public art collection, and a packed cultural and sports annual events calendar. This transformation is another success for the estate, with the number of non-professional headcount rising by 25% between 2022 and 2023, reaching an impressive 67 million visitors.

Renovation of existing office stock is a crucial aspect of this ambitious pivot to a mixed-use destination. In early 2022, American multinational investment bank and financial services corporation Citigroup announced plans to refurbish its prestigious U.K. headquarters, the 43-story Citi Tower located in the center of Canary Wharf. Upon completion in 2001, the skyscraper was the second-tallest building in the U.K. The Citi Tower project will be the first significant comprehensive office building refurbishment for the Canary Wharf Estate.

HDR is providing a wide range of building engineering services for Citi Tower, including mechanical, electrical, and public health (MEP) engineering, structural engineering, vertical transportation, technology consultancy, and energy assessments. Alongside this, HDR’s commissioning team has been appointed as commissioning manager for the project, working with the main contractor, Overbury.

One of the Largest Commercial Retrofit Projects in Europe

As the first major tall building upgrade within the Canary Wharf Estate, Citi Tower will create an elegant landmark. This highly ambitious project will be a leading example of the numerous benefits that can be achieved through comprehensive refurbishment, underpinned by creativity, technical expertise and imagination. 

Working alongside architects Wilkinson Eyre and TP Bennett, HDR’s specialist teams will transform Citigroup’s headquarters in Canary Wharf into a multidestination vertical village created for 21st-century hybrid working. This comprehensive refurbishment and remodeling is reported among the largest workspace renovation projects in Europe, spanning a 1.2 million-square-foot office plate and including new building services throughout, as well as 1800 on-site operatives.

The new design features a ground-floor entrance plaza and low-level welfare and amenity space to provide a stunning arrival experience for staff and visitors, complete with reception, a restaurant, auditoriums and visitor meeting suites. Major new structural openings create higher open space for the reimagined five trading floors accommodating in excess of 2000 traders and providing improved daylighting as well as an enhanced visual experience to support wellbeing and communication. Office stacks are separated into five stand-alone vertical villages; each three-level village features internal catering and welfare facilities, as well as internal atrium and staircase connection to enhance daylighting, well-being and communication. A new destination area, akin to a "town square", is created midway up the tower with winter gardens designed to bring the thermal line into the existing floorplate, providing a sensation of being in a cooler outdoor area; and incorporating a restaurant, gymnasium and a mid-level tenant entrance lobby. Executive floors located at the top of the building stack with large winter gardens and fully contained facilities include executive meeting rooms, luxury catering and a wellbeing offering.

Automation, Efficiency and Control

The refurbishment involves a full design replacement and upgrade of MEP services, with a focus on improved resiliency and energy efficiency. Our experts reimagined the building engineering services in 3D modelling throughout all stages of the project, and in coordination with other disciplines. The model contains 6,500,000 components. The new office fit out offers a fully automated MEP services installation developed with our in-house building management system (BMS) engineers, connected to a centralized BMS providing full monitoring, control and data log. Temperature and carbon dioxide sensors are provided in all areas to monitor and control the temperature and air flow rate, depending on demand and the movement of occupants to achieve a high energy efficiency performance. Additionally, we employed localized, combined control plates to the cellular spaces to allow occupants the capability to control the environment, for example via adjusting the lighting character or blinds control.

HDR's design increases the overall building occupancy by 20%; the new ventilation solution delivers a further increase to the fresh air output, with the capacity expanding from 10 liters per second per person (l/s/person) to 16 l/s/person, which in turn is a key consideration when obtaining the WELL Building Standard credits. The project is targeting WELL v2 Graduated Platinum and WELL v2 Core Platinum for tenanted areas. 

HDR's integrated communications technology (ICT) early works package on the project includes IT infrastructure design and resilient ICT backbone throughout the building, including 45 comms rooms and a 160-rack data center with support areas. Our design enhanced connectivity, resilient infrastructure and comfort and control of utilities and data. Smart aspirations for the building include live monitoring and controlling of MEP systems, ability to introduce day-two intelligence software and hardware, providing flexibility to the space, as well as analytic tools allowing for predictive maintenance, subsequently reducing operational costs and enabling plant improvements. In terms of health and well-being, we are designing to introduce dedicated apps that connect staff and workspaces, to improve occupant comfort and to provide desk booking and footfall occupancy data with the potential to inspire beneficial office layout changes.

The renovation of Citi Tower presented a variety of complex and idiosyncratic challenges. The existing structure of the building, including the constraining fixed variable floor-to-floor heights, meant that there was no capacity for additional lift cores and the output of the existing ones needed to be increased significantly. Collaborating with Vertical Transportation Studio, our team developed in-depth simulations of several options, including double-deck lifts and twincar lifts; eventually settling on an innovative combination of single and double-car lifts. This solution effectively reduces waiting times and congestion, whilst increasing the number of people journeys by 50%, from 2000 to 4000 per day; a total of 65 lifts are incorporated into the existing structural core, which originally housed 42.

Additional challenges effectively addressed by HDR teams included coordination of services with extensive structural modifications, accommodating the high extract flow rate requirements of the catering facilities and the cold room storage. This met the fire engineering and smoke control requirements. The four-story basement was converted into changing facilities and subsequently required a brand new bespoke smoke extraction system. 

HDR’s energy modeling has informed bespoke engineering designs, for example, computer room air conditioning units that use energy-efficient free cooling when external temperatures are favorable. This has contributed to Citi Tower targeting BREEAM Excellent and LEED v4 Platinum certifications, as well as a predicted upgrade of the EPC rating from D to B. This approach will help prepare the client for the expected energy-efficiency regulation change in 2030 and beyond.

Collaboration

One of the key considerations for HDR across this project has been collaboration and effective communication with the client, our industry partners from across the built environment and internal stakeholders. Our holistic multidisciplinary approach has permeated throughout this project, with a variety of teams coming together, each contributing their respective expertise. Four HDR offices across the U.K. and U.S. are involved in the refurbishment of Citi Tower, with up to 75 of our experts from the U.K. offices during peak production times.