"This is not a decision which the board and management of EQC decided to take alone," Wintringham said. "We took that decision after sounding out from the government and government advisers about the degree of fiscal risk the government was prepared to take. There is a significant cost in terms of our reinsurance."
The annual EQC levy was hiked to $207 from $69, while private insurance premiums had only doubled, based on anecdotal, chief executive Ian Simpson said.
Wintringham said affordability of private insurance depends on the ability of insurer to offset its risk with reinsurers.
"We're seeing a significant step up in pricing - maybe famous last words, but my judgement is that's peaked and we will start pulling back from that," he said.
Canterbury Earthquake Recovery Authority chief executive Roger Sutton, appearing at the same hearing, said New Zealand's level of insurance is very high, with 99 per cent of people in the Canterbury's 'red zone' covered.
Because many policies meant cover was uncapped, that surprised many insurers with how much they had to pay out, he said.
When asked whether the changing market dynamics may lead to underinsurance, Sutton said "we as a society need to think carefully about what they want to be covered for - do they want to be covered for trivia or things that really matter."
EQC's Wintringham said these questions are a fundamental part of the government's review of the EQC Act, which was announced in September.
The Treasury-led review will cover what the EQC insures, including the layer of loss covered, which natural disasters are covered, how multiple events should be treated, which types of property should be covered, the coverage of land, building and contents, what caps should be on the scheme, and whether it should be voluntary or mandatory.
CERA's Sutton told politicians that being able to get reinsurance money has been "extraordinarily important" in getting the rebuild underway.
His focus for the coming year is to accelerate the residential reconstruction and the anchor projects in the central city, and to bring private investment into the city, he said.