Screeds of tenants in cold, damp homes are speaking out about horrors of renting.

It's part of a Renters United campaign to improve the lives of renters by finding out just how bad their living situations are. 

Spokesperson Kate Day said around half of the country lives in rental properties but are made to feel like second-class citizens.

She said they plan to use people's real-life experiences in cold, damp homes as evidence to back up calls for change.

Ms Day said rental housing standards need to be improved and the Residential Tenancy Act overhauled - because lives are at risk.

"We have 1600 people that die year because of cold homes. We've got kids going to hospital for illnesses that could be prevented if their home was warm enough. Something has got to change."

She said more than 200 people have submitted their stories so far and the outlook's bleak.

Ms Day told Larry Williams one landlord's literally left their tenant in hot water.

"A guy had a broken hot water cylinder leaking hot water into his place. He got a power bill for $250 extra and his landlord wasn't fixing that."

"Mother with a really young toddler, they've moved to a place that's uninsulated and really cold and now they are getting sick about once a month."

Ms Day told Larry Williams many value having a stable home, over asserting their right to a safe one and many renters don't have the confidence to take their complaints to the Tenancy Tribunal.

LISTEN ABOVE AS KATE DAY SPEAKS TO LARRY WILLIAMS ON MIKE HOSKING BREAKFAST