An international fire expert says sprinkler systems are the “best protection” for older buildings such as New Zealand’s Loafers Lodge Hostel where six people died in a blaze this week.

The four-storey Wellington building was constructed in 1971 and had no sprinkler system in place. Police are treating Tuesday’s fire as suspicious.

“The building code does not require the retrofitting of sprinkler systems into existing, older buildings,” New Zealand Prime Minister Chris Hipkins told a press conference.

Melbourne-based Director of Basic Expert Jonathan Barnett, who hails from the US and testified before Congress on the collapse of buildings after the 9/11 terror attacks, says Australia has a similar approach and there will be many older buildings that don’t have sprinkler systems.

“If you look at Australia we do not normally retrofit sprinklers to buildings, except we have done so in aged care facilities,” he told insuranceNEWS.com.au.

“So the philosophy is the same as New Zealand’s. When there is a change in the building code we don’t require retrospective application of the code, unless we recognise the risk is too high.

“The philosophy typically is, well we’ve never had this happen before, and let’s not worry about it.

“Sometimes we have to be hit in the head to be shown the consequence and then we say ‘oh my God, we should have worried about it’, because although the probability was low, the consequence was high, and therefore the risk was unacceptable.”

Dr Barnett says he is a “strong advocate” of sprinklers in buildings that house vulnerable people. He says sprinklers not only protect lives, but also property, and make buildings more insurable.

“When a foreseeable event occurs that results in international headlines, that shows that kind of consequence is something that we ought to protect against and the best protection for these older buildings is always an automatic sprinkler system.

“In a fully sprinklered building, where the sprinkler system was designed and maintained appropriately, other than those intimate with ignition, we have never had a multiple life loss event anywhere in the world.

“The point is not just to advocate for sprinklers but to advocate for very high levels of fire safety. And often the most cost-effective way of providing that high level of fire safety is a sprinkler system.”