Professor Innes Asher says the Government could halve the number of children being admitted to hospital by fixing housing.

"I've had repeatedly people saying to me their house is making their children sick and it's very obvious as a health practitioner that that is the case," says Professor Innes Asher from the Child Poverty Action Group.

Housing New Zealand is being accused of not treating tenants with dignity or respect. Leading GP Dr Lance O'Sullivan has issued a challenge to create healthier state housing.

Dr O'Sullivan shared a video posted to Facebook showing water pouring down the inside of a window frame inside a child's bedroom at a Housing NZ home.

A four-year-old child who sleeps in the room was brought to see him, "chronically unwell and sick with asthma and respiratory problems".

He says poor housing is sending people to hospital with chronic lung problems.

The Government's been swift to move into gear on the specific case Dr O'Sullivan highlighted, sending Housing New Zealand to the home.

But Dr O'Sullivan says it's a much wider problem than the one story he's shared.

Newshub.