The Labour leader's been accused of political grandstanding by trying to get cross party support for his rental house bill.

The bill requires all rental houses to have proper insulation, to be weathertight and to have adequate heating.

Housing Minister Nick Smith said the Government already has a bill in the pipeline that'd achieve that.

"The Government's bill will require all tenanted homes to be insulated by the first of July 2019. Labour's bill would not require that until 2023. How that meets the bill of being a guarantee of a healthy homes to me is a very long bow."

But Mr Little said that's not correct.

"Twelve months after the bill is passed, any new lease after then is required to meet those standards. Leases that continue, that have been in existence 12 months after, effectively have up to five years to meet the conditions unless that lease terminates and the property is re-rented to somebody else," said Mr Little.

LISTEN ABOVE: Andrew Little talks to Mike Hosking about the Healthy Homes Bill

Parliament will tomorrow debate Mr Little's Members' Bill.

The man who could swing the vote for Labour, United Future Leader Peter Dunne, isn't saying which way he'll vote.

"When the vote's cast in the house you'll know which way I'm voting."

But ACT Leader David Seymour is making it clear he'll oppose the Bill saying the solution to housing problems is to build more homes.

"Having a piece of paper saying that a particular home does or does not have a warrant of fitness, is not going to do one thing for people who are actually struggling with poor conditions."