Twenty-five buildings in Auckland, including more than half a dozen apartment blocks, have cladding of the type that burned on the Grenfell Tower in London.

Photo: AFP

Auckland Council identified the buildings and said they were all safe because they had various fire-protection systems such as sprinklers and alarms.

The council's new list showed 116 building sites with aluminium composite panel of different types. Of those, 25 had panels with highly combustible polyethylene cores which burned rapidly in the fatal Grenfell Tower fire in London in June last year.

Those included several inner-city apartment blocks, as well as Waitākere Stadium and the AUT Millennium sports complex.

Auckland Hospital was also among the 25 sites identified as having the cladding. Seven hospital buildings were named as having either highly combustible polyethylene core panel, or semi-combustible panel on them.

It was unclear how many of each there were. The council's list specified safety factors at the hospital such as sprinklers, or noted that the panel was a decorative feature only.

Another 38 buildings had semi-combustible panels, while the council was unsure what type of panels were on the remaining 53 buildings.

The apartment blocks with the combustible polyethylene core panels included Viaduct Point Apartments in Customs Street, Quest Apartment Hotel in Grafton Road, H47 Apartments in Hobson Street, City Garden Apartments in Albert Street, Nautilus in Orewa and Spencer on Byron in Takapuna

"The Auckland Council has holistically assessed the risk posed by ACP cladding in each instance and considers that a combination of fire prevention measures, fire safety systems such as sprinkler systems, the extent of ACP coverage and its exposure to an ignition source reduces potential fire risks and therefore does not cause immediate concerns for occupants' safety," Ian McCormick, council's general manager building consents, said.

"In each case we have informed building owners or the body corporate and have stressed that these buildings are not considered dangerous. We have encouraged them to notify their insurers and seek their own professional engineering advice.

"We've ensured the building owners are aware the presence of ACP cladding are on their buildings so they're able to make informed decisions. In many cases we would consider there's absolutely no reason to make any changes - in others, insurers may want to validate any perceived increase in vertical fire spread and build it into their premiums.

"Whilst in a limited number of cases the presence of ACPP material in the current context configuration may elevate the risk of vertical fire spread to some degree, we still consider in all instances that it is low risk.

"It's important to understand it does not make the building dangerous."

Last year the government tightened regulations on combustible external cladding.

"Council is working with MBIE [Ministry of Business, Innovation and Employment] specifically with regards to combustible cladding to ensure that the regulatory settings are appropriate and we are currently working with MBIE to put in place additional guidance to the industry specifically surrounding fire compliance of cladding systems," Mr McCormick said.

"We haven't identified any building that would be considered dangerous due to ACP cladding. It's important to remember that Auckland Council takes building safety very seriously and will not allow buildings to remain unsafe to the public."

The council said it was assuming a worst-case scenario when it did not know what type of combustible panel was on a multistorey building.

"What we're saying is we've assessed the cladding as being ACP PE, so that way we're assessing it as, if you like, the worst-case scenario," Mr McCormick said.

Generally, the council consents showed what type of panel a building had been consented to use.

However, this investigation used a specialist team that set a higher bar to find evidence of what was actually put on a building, he said.

Product substitution of cheaper products in place of what had been consented has been an ongoing major problem for the council, at least in residential building.

The team had also assessed the danger of burning panel debris falling off buildings, and of fires spreading from these buildings to others nearby, when it judged that all of the buildings were safe.

See the list of Auckland buildings that appear to use ACP cladding to some extent: