Building and Construction Minister Maurice Williamson said five years ago there were 22,000 properties requiring more than $3.6 billion in repairs.
PriceWaterhouseCoopers was undertaking a review which was likely to find "considerably more" problem homes.
There will be further houses yet where the problems have not yet surfaced, Mr Williamson told Parliament's social services select committee today.
He said the focus of the Weathertight Homes Tribunal needed to shift to fixing the problem instead of paying fees to lawyers.
The Government was looking at what was being done in similar international situations.
Canadian pensioners do not pay anything up front to have their homes fixed, but the amount is taken out of their estate when they die, which was one option, Mr Williamson said.
Things "cannot be left" as they were -- one Waitakere woman was using a rubber stick to turn her light on because water was running down the wall, he said.
"I'm not a bloke who resorts to crying a lot, but I've sat in a room where I've nearly found myself in tears when I've seen the circumstance that some people are having to go through.
"It's their greatest asset...and it's just turned to something that in some cases has negative equity -- if they walked away they would still owe money on it." However, he said, we learnt a "big lesson" as a nation and the country needed to move on.
"I think we should move on as a nation and forget about which one of the responsibilities was but make sure we get things in place to fix it." Problems with design, product, cladding, low skilled workers, rules and checks were all to blame in different houses, Mr Williamson said.
There may be a need for "another way" to certify the structural integrity of houses and leave compliance and health and safety checks to local authorities.
Changes to regulations mean houses built in the last year would not suffer from leaky home syndrome, he said.
