Once inside the home, inspectors found several dozen violations like faulty wiring, illegal conversions and blocked exit.
The red tag outside 18 White Street on Wednesday indicates the property is off limits as officials sort out the conditions they found inside.
Last Thursday, Spring Valley police responded to a call of an unconscious baby and the 6-month-old child was pronounced dead at an area hospital.
Police say there were eight other kids in the house at the time, prompting an investigation into whether an unlicensed day care facility was operating at the location.
Neighbors said they had no idea of the conditions next door, but the buildings department found 51 violations during an inspection.
"Ranging from lack of smoke detectors, carbon monoxide detectors, egress paths, windows that have been boarded up, the illegal conversion of the garage into a living space," said Ed Markunas with the Office of Buildings and Codes.
Illegal conversions have long been a problem in Spring Valley - so much so that the county has taken over inspections in the village.
One woman said she lived in an apartment in the house, but claimed she was unaware of illicit activity.
The kids had been removed from the location by the time the buildings department conducted its inspection.
Officials say there was nothing obvious that points to a day care facility.
"The inspection didn't reveal any cribs, any type of nursery style equipment, high chairs, the only thing that would have been recognized were a few car seats," Markunas said.
A total of $42,000 in fines has been assessed against the landlord, Joel Friedman of Spring Valley, who could not be reached for comment.
The buildings department says it does not appear anything in the home contributed to the child's death, which remains under investigation by police.
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