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Can we have an article update please? 18.104.22.168 (talk) 18:39, 24 April 2014 (UTC)
Energy-savings questioned, the term is "double-skin facade"
Quote from the article:
The building uses energy-saving methods which allow it to use half the power that a similar tower would typically consume. Gaps in each floor create six shafts that serve as a natural ventilation system for the entire building even though required firebreaks on every sixth floor interrupt the "chimney." The shafts create a giant double glazing effect; air is sandwiched between two layers of glazing and insulates the office space inside.
I'm pretty sure the correct term to use here is double-skin facade. Quote from 2013 article on the building from ArchDaily:
The double-skin façade zones encased by clear glazing presume that air between curtain wall layers will absorb solar heat, rise due to the stack effect, and vent to the exterior through narrow slits at the top of each two-story structural bay.
Also, the windows have been rarely used since they started falling off and some tenants have sealed off the curtain wall for security reasons, pretty much ruining any claimed energy savings, according to ArchDaily:
A notable case is London’s sustainability-hyped “Gherkin” (Foster & Partners, 2003), where the building’s open-floor ventilation system was compromised when security-conscious tenants created glass separations. Operable windows whose required specifications had been lowered because of the natural ventilation feature actually began to fall from the building, and had to be permanently closed. The ambitious goal of a more sophisticated natural ventilation system paradoxically resulted in even worse ventilation.
One of the building’s operable windows broke off and fell some twenty-eight floors to the ground. Building managers concluded that one of the mechanical arms controlling the window had failed.  Following this episode, Swiss Re and its management company disabled the mixed-mode building control system as they tested and replaced the chain-drive motors controlling window operation. The system has been used on only a limited basis since. Many tenants have walled off the atria, and some have insisted on lease provisions guaranteeing that mixed-mode ventilation will not be employed in their zones. Since 2005, as far as I can determine, the windows have opened only occasionally and only on the lower floors, which are occupied by Swiss Re. This means that mixed-mode ventilation is available in only one of the four sets of six-story atria. For all but its first year of operation, then, the building has run primarily on mechanical ventilation. [...] I have been able to determine the performance of the mixed-mode ventilation has never been rigorously tested or empirically confirmed. [...] Nor has this hybrid of ventilation systems been employed in another tower before or during the decade since the design was completed, which suggests that neither the firm that designed the Gherkin nor the profession at large sees this as a valuable approach. The combination of double-skin facade, atria, and open floors connotes improved environmental performance and aligns the building with symbolically powerful precursors. But what it yields functionally is an internally incoherent environmental control system of undetermined performance capability. [...] If its provisions for natural ventilation are not used, 30 St. Mary Axe is not a green tower but an energy hog.