A bill requiring rental properties to meet a minimum standard of heating, ventilation and drainage has passed its first reading in Parliament.
The Labour party's Healthy Homes bill, which goes further than the government's plan to insulate rental homes, had the support of United Future, Maori Party, New Zealand First and the Green Party.
National and ACT opposed the bill.
Labour leader Andrew Little said just having insulation was not enough.
"Particularly in the middle of winter, having good insulation, all that does is keep the cold in, so the standard needs to include a source of heating and it needs to include good ventilation.
"The reason why mould and stuff gathers in a house is because it's not well ventilated, that's the stuff that's making kids sick."
United Future leader Peter Dunne's support was qualified. The bill needed to ensure homes remained affordable as there was no point providing heating if renters could not afford the increased cost of electricity, he said.
The bill will now go to select committee stages.