Two women were doing the dishes in the rear of an Auckland dairy when the floor collapsed beneath them on Christmas evening.
The two women became trapped in the hole, which opened up around 6pm last night.
One woman was pulled from the hole and the second had to be rescued by fire services. Both suffered minor injuries.
"They were doing the dishes when the floor suddenly collapsed," said Raj Chopra owner of the Crown Superette in Mt Roskill and the building's tenant, whose wife fell into the hole.
He blamed the building's age and the landlord's lack of maintenance for the accident.
"The floor just collapsed. The landlord is not going to take any responsibility. Not one nail has been put in this building in the last three years," said Chopra.
The fire service have stabilised the floor but a large hole remains and a horizontal ladder is being used to cross the collapsed area to access the rest of the building.
The property is without water and telephone and lost its eftpos connection for some hours.
The store was open yesterday and remains open today but Chopra said his business had been affected.
"It is very hard for me to run the shop like this and it is impossible for me to shut the shop."
The Chopra family, who have lived and worked at the Superette for 14 years, said the landlord who had taken over the property three years ago attempted to make them responsible for the structural maintenance.
"There are many issues the landlord has not fixed. We need help from the council because the landlord is doing nothing," Chopra said.
The Department of Labour and the Auckland Council have begun preliminary investigations into who was responsible for the maintenance and safety of the building.
The landlord could not be reached for comment.