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Adexsi cools the Walkie Talkie

Photo of Walkie Talkie gardens

Smoke and natural ventilation specialist Adexsi UK is playing a key role in the success of one of the City of London’s latest landmark buildings.
20 Fenchurch Street, which is better known as the ‘Walkie Talkie’ due its distinctive curved shape, was finally completed last month with the opening of its spectacular ‘sky garden’ above its 34 storeys of commercial office space.
At a 160m (525 ft) tall, it is London’s fifth highest building and cost £200m to build. The sky deck provides three floors of viewing space along with bars and restaurants – all open to the public – within its unusual forward leaning upper level.
The roof garden is heavily glazed to provide excellent views of the city and across the Thames. However, the amount of glazing does increase the risk of overheating due to solar gain.
Adexsi, because of its particular expertise in this area, was asked to design, supply, install and commission a system that would keep the space cool; deliver adequate ventilation for the occupants and visitors, but also provide smoke extraction in the event of a fire. All this without compromising the visual impact of this stunning building feature.
The chosen solution was the Adexsi Veriflow system that can provide daily ventilation, but is also able to switch into smoke ventilation mode in case of fire. The system features a series of low and high level dampers operating discreetly behind the building’s cladding fins and external/internal louvre systems.
The dampers were installed inside the curtain walling, which was designed by the cladding specialist Josef Gartner, and they operate in a gap of just 180mm.
The damper controls are linked to the Walkie Talkie’s building energy management system (BEMS), which ensures the system is fully modulating and that the appropriate number of low and high level vents are open to meet changing ventilation requirements at all times of the day and night.
“We are delighted to be playing such an important role in the successful operation of a true London landmark,” said Adexsi UK director Rob Davies. “This is also part of a growing trend to engineer systems that can operate as both day-to-day ventilation and as smoke extractors in the event of a fire.
“We are seeing increasing demand for this kind of solution as it allows end users to maximise the payback on their investment by meeting safety and comfort requirements with one system. However, to do this properly requires close collaboration between the ventilation specialists and the rest of the building’s design team – something we were delighted to experience at the Walkie Talkie.”