30 St Mary Axe
30 St Mary Axe (widely known informally as "the
Gherkin" and previously the Swiss Re Building) is a skyscraper in
London's main financial district, the City of London, completed in
December 2003 and opened in April 2004. With 41 floors, the tower is 180
metres (591 ft) tall and stands on a street called St. Mary Axe, on
the former site of the Baltic Exchange, which was extensively damaged in
1992 by the explosion of a bomb placed by the Provisional IRA.
After the plans to build the Millennium Tower were
dropped, 30 St Mary Axe was designed by Norman Foster and Arup engineers,
and was erected by Skanska in 2001–2003.
The Gherkin’s famous bulging shape can be clearly
distinguished from beyond the City and as far away as the M11, 20 miles to the
east. In 2004 it won the UK’s top architectural accolade, the Stirling prize,
with judges hailing its unique design as “elegant and impressive”.
Yet the tower’s powerful and enduring wow factor is not just
a bonus: it is an essential part of the building’s function, as the companies
that occupy the Gherkin use it to promote themselves. For many tenants, the building’s
appeal to clients is what justifies the annual rent of up to £750/m2 a year,
nearly 15% higher than other top-grade City offices.
“Why did we move here? Because of the prestige of the
building,” says Fiona Eldridge, office manager of Primus Guaranty.
“Every seminar we hold here is a sell-out,” adds Linda
Felmingham, administrator at City law firm Hunton & Williams. Half of one
of its two floors is filled by four meeting rooms that can be opened out into
one large conference suite for more than 100 people, with its own fully
equipped kitchen. “It’s amazing how everyone wants to come to this building. As
a result, many doors have opened for us,” says Felmingham.
The Gherkin is still promoted as “London’s first ecological
building” on Foster + Partners’ website, which claims that it “will use 50%
less energy than a traditional prestige office building”. Yet Stead, the
building’s property services director, admits that “40-50% energy savings are a
bit over-ambitious, because Swiss Re is the only tenant using the efficiencies
of natural ventilation through opening windows and no internal partitions to
block the air flow”.
The building was designed to admit natural ventilation
through windows that open right up to the 32nd floor, when the wind speed is
below 10mph and the external temperature is between 20°C and 26°C – that is, up
to 40% of the year.
“We try to sell the whole energy package to every new tenant
through their M&E consultant,” says Steve Brown, the building services
manager. Unfortunately his exhortations have so far fallen on deaf ears, as all
tenants except for Swiss Re have opted for full, all-year-round
air-conditioning.
“M&E consultants want maximum comfort for their clients
and air-conditioning is more controllable than natural ventilation,” says
Brown. “In addition, legal, financial and insurance companies want maximum
confidentiality, so they have put up glass partitions round their offices, and
that leaves nowhere for the fresh air to go.” The financial savings to be made
by reducing air-conditioning is little incentive for firms that pay up to
£750/m2 a year in rent.
Other than trouble with natural ventilation, occupants find
the internal environment comfortable. “We don’t suffer from too many hot or
cold spots,” says Campbell. “And the noise level is very good.”
Felmingham says: “The air-conditioning is always superb, and
I’ve never said that about the other buildings we occupied in the City.”