AWARD – Sky Innovation Centre, London

Showcasing structural engineering excellence to reduce carbon by advanced analysis, this minimalist building creates an inspiring working environment for a hybrid workforce.

FACT FILE
Architect: AtkinsRéalis
Structural engineer: Arup
Client: Sky

The Sky Innovation Centre, which represents the latest phase in the redevelopment of the media company’s west London campus, is a building said to include impressive wellness, sustainability, and environmental performance credentials.

The architecturally striking building was delivered with a significant focus on driving down embodied carbon, reducing waste through prefabrication and efficient design, and ensuring materials were responsibly sourced. 100% of construction waste was diverted from landfill, and with its supply chain partners, the main contractor says it eliminated the majority of single-use plastic packaging during construction.

A project spokesman, said: “The incredible collaboration and innovation between every project stakeholder has led us to this successful outcome. The journey doesn’t end here however, as this new facility will now allow Sky to continue to push the boundaries of consumer technology and further their technical expertise.”

Occupying the site of two former buildings, the new three-storey steel-framed building has been designed to maximise natural light within the majority open plan accommodation. The exterior features a ziggurat-style façade with splayed columns, while internally, a full height atrium is flooded with daylight. Topping the building, a large photovoltaic (PV) array generates emission free electricity.

The building creates an inspiring new space where Sky’s most inventive, forward-thinking minds can come together to match customer insight with rapidly changing technology requirements.

It showcases excellence in holistic sustainable and user-centred design, while supporting Sky’s ambitious net-zero vision. The building has achieved BREEAM ‘Outstanding’ and WELL ‘Platinum’ ratings.

Steelwork was chosen for a number of reasons, one of which was speed of construction. The frame was faster on site and required less trade coordination than alternative framing solutions.

Using steelwork also helped the project team maximise offsite construction, which enabled the job to progress during the COVID-19 pandemic. With fewer workers on site, the steel erection team were able to ‘bubble’ themselves and maintain effective COVID protocols, which resulted in minimal impact on the delivery programme.

The steel frame creates floorplates that are column-free, with perimeter columns more closely spaced to provide direct support to a series of primary trusses. In this way, 13.5m-wide spans have been efficiently achieved with a minimal steel tonnage.

The trusses T-plate bottom chords minimise visual appearance, while facilitating simple welding of truss nodes. The internal visual impact of the trusses is further reduced by integrating the top chord box section into the depth of the slab.

During the design phase, several options were considered for the slabs. The choice of hollowcore slabs have provided a durable and robust solution that gives enough mass to control dynamic footfall response.

Arup says the highly efficient, beautifully crafted minimalistic steelwork trusses are integral to the architectural feel of the building and they are created with advanced structural analysis and design, achieving a steel weight of 35kg/m² for the floors.

The primary steel frame geometry is linear and regular for direct load paths and ease of construction. The eye-catching ziggurat façade is formed with shaped secondary steel members. This is said to have enabled the primary frame fabrication to start, while final façade coordination continued, shortening the critical programme path by two months.

The design and the use of splayed columns has helped reduce stress and deflection in the primary beams. They have also improved the footfall response of the slab, while also providing stiff landing points for atrium stairs connecting onto the floorplates. This is said to have saved 19% CO₂e compared with vertical columns.

“Beautifully detailed trusses, elegantly tapering splay columns and flat soffits provide Sky’s desired sophisticated industrial look and feel,” says Arup Engineer Tim Snelson.

“We were able to design-out ceilings and other finishes, thereby substantially reducing the overall building embodied carbon.”

A further embodied carbon reduction was achieved by designing-out any structural topping for the internal slabs, by using strut and tie finite element analysis for in-plane forces. This allows future disassembly and potential recovery of the structure.

Inside the building, a timber-hybrid mezzanine enables further disassembly and reconfiguration of the atrium. The mezzanine framing was a late addition to the project, so the team designed it to be constructed from lightweight components that could be installed with low-level handlers, after the roof was built.

The client wanted adaptability for the mezzanine level, which weaves around the atrium and so cross laminated timber (CLT) slabs supported by the steel frame were chosen.

The available headroom was limited, so the CLT planks are integrated into the steel beam zone. The mezzanine grid is distinct from the primary column pattern, with the planks spanning between 6m and 7.5m onto the steel beams.

The modest column grid achieves a 300mm structural zone without using excessively heavy beams, and is supported through the ground floor slab.

“We had a clear vision to create a unique and responsible building, steeped in our ethos to do the right thing for the environment and our people. Staying true to these principals and using learnings from previous experience helped us make brave decisions, challenge industry standards and deliver even better outputs,” says Diana Foxlee, Director Sky Spaces.

“Working with teams who shared our vision allowed us to lead the way in reducing embodied carbon and single use plastics and to thoughtfully source materials, suppliers and subcontractors, setting out a successful blueprint for the way we’ll work in future construction.”

In summary, the judges say this minimalist structure, comprising highly optimised steel floor trusses, supported on splay columns to reduce bending, maximises design for disassembly. A key aim of the client, adopted throughout the supply chain, was to minimise environmental impacts. The result is a very adaptable, high quality workspace with excellent sustainability credentials.