Black mould was visible on the inside of some windows, along windowsills, curtains, and on the walls, she told the broadcaster.
"It's disgusting and there's mould up on the curtains and the window ledges and everything. It's a real big worry."
Ms Wensor turned down the property.
She had been reassured she would not lose her place on the priority list by doing so, she said.
In a statement to Radio New Zealand, Housing New Zealand said the property would have undergone a full maintenance and repair check before a new tenant moved in.
It would continue to look for a house for Ms Wensor, it said.
On Friday, Ms Wensor described how the Glen Innes house was so mouldy there were holes in the walls, and she feared she would wake up one day and her son would not "be there anymore".
"All the mould from the bathroom is just coming through to the walls. Because the water's coming straight down from the inside of the wall, coming down to the bottom, and it's just rotted all the wood on the side of it."
Last year one of her sons fell against the wall and went straight through it, she said last week.