The Auckland skyline featuring the new Commercial Bay. Photo / Jason Oxenham
The NZ International Convention Centre fire has raised questions about the safety of other large Auckland buildings, particularly soaring new blocks like the PwC Tower at Commercial Bay.
Parts of that $1 billion 40-level tower have aluminium composite panel cladding (ACP), but not the same material which Auckland Council hasinvestigated as a potential fire hazard.
Both the council and the tower's owner say the ACP on the nearly finished waterfront tower - where 3000 people will work - is certainly not the highly flammable material like at London's Grenfell Tower which burned down, killing 72 people.
Jeff Fahrenson, the council's field surveying manager, said the PwC Tower had many different types of cladding, mainly glass in the form of a glazed curtain-wall system.
"There are smaller, isolated areas where ACP cladding has been used - such as the upper floor plant room and also where it is used to conceal the structural frames where they protrude out past the glass façade," Fahrenson said.
But he indicated PwC's cladding - although partly ACP - was not like that at Grenfell.
"The ACP used has a modified core, making it fire resistant, which satisfies the fire-testing requirements as set out by the Ministry of Building, Innovation and Employment in the Building Code. There are currently compliant ACP claddings available in the market which can be used to clad buildings in New Zealand," he said.
Landlord Precinct Properties says it will soon accommodate 10,000 office workers in five of its towers within just two blocks - the most highly concentrated workforce anywhere in New Zealand:
• New PwC Tower at Commercial Bay, opening next year. • The existing PwC Tower on the Lower Albert/Quay St corner. • Zurich House at the foot of Queen St. • The AMP Tower on the Lower Albert/Fanshawe St corner. • 1 Queen St beside the new PwC Tower.
Scott Pritchard, chief executive of Precinct Properties, which owns the PwC tower, said the vast majority of the cladding was a curtain wall glass façade with an expressed diagrid on the east and west side, which is an aluminium composite fire-resistive, non-combustible metal panel.
And in the event of a fire, the tower had full protection, he stressed.
"Currently, there is a fully charged hydrant riser system to the top of the tower to enable emergency services to plug in locally should it be required," he said.
Numerous fire extinguishers are already provided on every level and detailed processes regarding hot work permits and clearly detailed emergency and evacuation plans were in place, he said.
"Post completion, the tower will have a sprinkler system, smoke-detection system, zone pressurisation system as well as a staged-evacuation programme for the safe evacuation of all occupiers," Pritchard said.
In the new PwC tower, 80 per cent of offices or commercial space are leased. Alvarium will be on L37, PwC has leased space and has naming rights, law firms Chapman Tripp and MinterEllisonRuddWatts will also move there and DLA Piper, Regus and Spaces are other new tenants.
Last year, the council released a list of Auckland buildings with ACP cladding after examining 300 buildings of which 147 had the cladding.
Within the buildings investigated, there were more than 5000 residential apartments and hundreds of commercial offices, it said.
Twenty-five of the buildings investigated had exterior aluminium composite claddings like at Grenfell Tower but the council stressed those with the flammable polyethylene cores in their claddings were not necessarily dangerous because they had other means of fire protection - which weren't available to the Grenfell victims.
The Herald reported the list as including the huge Waitakere Stadium at Henderson, certain Auckland Hospital buildings in Grafton, Spark's four-building campus in Victoria St, large residential blocks in the Viaduct and CBD, the huge PwC building on the city's waterfront, TVNZ's headquarters on Victoria St, Auckland University's Owen Glenn Building and many apartment blocks.