Children start about 700 fires a year, at an average annual cost of about $8 million.
Information obtained by the Herald on Sunday revealed at least 1400 fires were lit by children under 16 in the past two years. At least 375 of those were started by children under 10.
The Fire Service conceded the numbers could be higher because deliberate acts were under-reported because of industrial action during that period, when firefighters did not complete incident reports.
New Zealand Fire Service's fire awareness and intervention programme manager Peter Wilding said three homes were destroyed in Auckland last month by children under the age of five who had been playing with lighters or matches.
Wilding said most fires lit by younger children were reckless but not necessarily an act of arson, which meant children needed education rather than punishment.
"If an adult did it, it would be an act of arson, but we have laws in New Zealand where a child won't go through the justice system. They will be referred to youth aid or to the fire awareness and intervention programme," Wilding said.
"Most of the children who light fires are not intending to cause damage. We are sure of that because when we interviewed children they did not realise the fire would grow bigger."
The number of referrals by authorities, schools and concerned parents for children to participate in the awareness programme had increased in the past two years.
"This means a significant number of children are still lighting fires," Wilding said.
One case involved a toddler who rolled his father's lighter along the carpet like a toy car, setting his family home on fire, causing $247,500 worth of damage.
Fire safety officer Kevin Collins said the 2-year-old boy was playing in his bedroom when a spark from the wheel of the lighter ignited the foam carpet underlay, creating an out-of-control blaze within minutes.
"The fire went like a rocket. He's lucky to be alive," Collins said.
Other serious cases involved children, aged between 11 and 16, who destroyed schools by deliberately setting them alight.
During the past two years Timaru Girls High, Kerikeri High School, Wainuiomata College and Rongotai College were set alight, causing at least $1 million worth of damage to each school.
Auckland's Mangere East School also went up in flames at the hands of a child, causing $410,000 worth of damage.
The Fire Awareness and Intervention Programme is free for children who have lit fires or expressed interest in fire. The programme is usually delivered by firefighters during two sessions which catered for the appropriate age group. Younger children will learn about different fire-starters that shouldn't be touched and older children view graphic images depicting the consequences of fire.
Any child under 18 who has fire-lighting tendencies.
Parents, caregivers and authorities can make referrals. Firefighters who attend incidents involving youth will also recommend the programme. To make a referral call 0800 FIRE INFO
More than 500 children are referred each year and 98 per cent of children stop lighting fires once the programme is complete.