Plunket is joining the call for vulnerable families to be given more help his winter.
The child advocacy group is concerned that young people living in cold, damp homes will struggle with the colder months ahead.
National child safety advisor Sue Campbell says landlords need to be proactive.
"We're all very aware that a house that is well ventilated, is warm, and draft-free as much as possible, does provide a healthier environment for everybody, including the children," she says.
Plunket is also urging parents to keeping heaters and fires away from children. While Plunket is concerned about those living in cold homes, it says families with heat are just as deadly.
Ms Campbell says it's a dangerous time for children.
"Think about the 'metre from the heater' rule," she says. "It's all about helping prevent burns, just being very aware of the safety of the children."
Plunket says landlords also need to ensure that homes are up to scratch.