Vast majority of NZ's multi-storey buildings have weak points

The vast majority of the country's multistorey buildings have substandard fire protection, a fire protection specialist says.

Multiple warnings about poor protection against the spread of fire have been issued since 2008. But there is widespread industry agreement that most buildings have weak points that could accelerate the spread of a big fire and shouldn't have been signed off as compliant with the Building Code.

Fire protection specialist Ron Green said he had seen rest homes without firewalls above the ceiling and holes in hotel walls without fireproof seals - or the wrong ones.

He had come across steel frames painted so badly with expanding intumescent paint - which expands in a fire to protect the material underneath - that it had cost $300,000 to fix.

Mr Green said he could not name buildings for contractual reasons but he had been "shouting about" the issue for a long time.

"People often say, 'Well, what's the chances of a fire happening here?'

"The Grenfell disaster, as horrible as it is, has made people aware that things can happen. I've always said it would take a disaster in New Zealand for it to be taken seriously."

Since the Grenfell Tower fire in London last month, the government and fire engineers in New Zealand have repeatedly said that most high-rises have sprinklers installed so are safer than in the UK.

But "passive" measures designed to stop fire and smoke spreading - such as firewalls and fireproof sealant - have been faulted for years.

The Building Minister Nick Smith was unavailable to speak with RNZ this morning.