A major stoush has broken out between the Housing Minister and Treasury with Phil Twyford slamming some of those working at the Government's lead economic and financial adviser as "kids."
That's after Treasury downgraded its forecast over how much extra housing investment Kiwibuild will deliver to the economy.
Builders are under the pump and construction is being delayed on some new houses by at least a year.
"We're really busy as an industry and just forever I get reports of builders wanting more and more people. And they're just not available, so we're in a pretty chronic position currently," Grant Florence of the NZ Certified Builders Association told 1 NEWS.
It has prompted Treasury to downgrade its forecasts for the Government's Kiwibuild programme.
"I just think some of these kids in Treasury are just fresh out of university and they're completely disconnected from reality," Mr Twyford said.
National's housing spokesperson Judith Collins said her experience is "you should always listen to Treasury".
"They're not always going to be exactly the way they see things, but ultimately they're looking at it from a dispassionate point of view and independent point of view," she said.
Before Christmas, Treasury said Kiwibuild would result in $5.4 billion of extra residential investment by 2022.
Now it has slashed that number in half, saying some of that investment won't happen as quickly.
"One of the mistakes I think Treasury have made is that they've assumed that the investment has to be made before the houses are built," Mr Twyford said.
The Government has also promised to build 1600 state houses a year.
Currently there are almost 8000 households in need of state housing and National says it would have built more.
"National went into the last election promising over 6,000 state houses over the next three years. So we were promising on 2000 a year," Ms Collins said.
Mr Twyford said: "The opposition had nine years and they allowed the housing crisis to spin out of control."
The Government is promising there's no change in its plan to build more houses, and there will still be 100,000 affordable homes in a decade.