"Rental is the biggest factor," he said. "It often leads to doubling-up, more people in a home, it puts pressure on the families, then it blows up, and then there are more people who are struggling."
In a media release yesterday, the army said it helped more than 120,000 adults and children nationwide with emergency food parcels, or accommodation and other support services, last year. Of them more than 68,000 were aged under 18. The army provided a further 89,020 "bed nights" to individuals and families who would otherwise have been homeless.
The release said: "When housing prices are rising faster than wages and salaries, ministries across the nation are reporting the number of those living in unsuitable environments, on the streets or in cars, is growing."
Major Irwin said the need was "definitely" much greater.
He cited one example of a woman and her preschool-aged granddaughter living in a single room in a boarding house mainly occupied by troubled men, until the Salvation Army intervened and relocated the pair.
Such "harrowing circumstances" were not uncommon, but the organisation has found itself struggling to cope with the need and has "moved towards being the ambulance at the top of the cliff", with services aimed at helping people recover from their circumstances.
People applying for food grants need a referral from such agencies as Work and Income - which one Napier woman said was actually a "rejection" letter - and applicants are interviewed about their need and how they can be helped to turn their situation around.
Applicants are unlikely to be provided with a food parcel more than three times a year, although there may be some further help if they become "actively engaged" in budgeting advice, life skills courses and other strategies.
A Napier woman, who is a CYF-registered caregiver with several children in her family's care, but who has also had to call on foodbank help, said yesterday the need was much greater. She said it was clear those providing the services were struggling to cope with the need.
About 450 people, drawn from Salvation Army members and other volunteers such as Rotary clubs, will be on the streets from today to Saturday.