The Department of Housing has said it was not aware that up to 70 people were living in a Dublin property and that any action taken would depend on the local authority or the Chief Fire Officer.
It emerged yesterday that a property management company in Dublin is renting a number of houses to up to 70 people at a time, with 15 sleeping in some rooms.
The owner of two properties implicated said he leases the houses to the company and allows them "to do what they like with them".
"There's no breach of regulations," he said.
One house, in Lehaunstown, Cabinteely, has around 70 people living in it, but there are only two showers.
A spokesperson for the Department of Housing said: "We haven't been notified about the property in Cabinteely.
"Overcrowding may give rise to concerns in respect of fire safety and may lead to enforcement action by fire authorities.
"Minimum standards for rental accommodation are prescribed in the Housing Regulations 2008, as amended.
"The regulations specify requirements in relation to a range of matters such as structural repair, sanitary facilities, heating, ventilation, natural light and safety of gas and electrical supply.
"With very limited exemptions, these regulations apply to local authority and voluntary housing units as well as private rented residential accommodation.
"All landlords have a legal obligation to ensure that their rented properties comply with these regulations."
Dun Laoghaire-Rathdown County Council did not respond with a comment when contacted by the Herald yesterday, and Dublin's Chief Fire Officer could not be reached for comment.
A former tenant described the living conditions in the house as "disgraceful and dangerous".
"When I moved in, my room was in the basement," he said.
"The other tenants were like, 'You do know the ceiling above you has completely collapsed twice during parties?' and 'Oh you have a window, lucky you'.
"People all had yellow fungal diseases on their feet as there were only two showers at the time for the whole house. You wouldn't have washed a rat in them."
Jordan Rhodes (21), originally from Newcastle, lived in the house for two months due to "desperation".
He said that when an electrician called round one day, he told the tenants that if he had not fixed a problem with the fuse box, the house "could have been burned to the ground".
"When I moved in, there were around 40 people living there, mostly South American and Eastern European," he added.
"When I left, there were around 70, after they put more bunk beds in the basement.
"There are extension leads all over the house because there are so many people living there.
"I was told that the house was cleaned three to four times per week and that bin bags and toilet roll would be provided at all times, which of course wasn't the case."
A man who works for the property company uses the name "Dyl O'Reilly" to advertise properties on Facebook.
"It's not great, I wouldn't even show it to you as you're Irish," he said when asked if it would be possible to rent the house in Cabinteely for €200 a month.
Another property managed by the company, in the Rathmines area, has between 20 and 40 people living there - all females. The owner of the property denied any knowledge of this and advised us to take the matter up with the management company.
The properties in Cabinteely and Rathmines are not registered with the Residential Tenancies Board.
It is not known exactly how many houses the company is managing across Dublin.
The firm is run by a father and son. The son has denied any involvement in the properties and said that, as of two weeks ago, the company had been passed over to new owners.