The fire began shortly after midnight Thursday in Residence du Havre in the small town of L'Isle-Verte, 130 miles northwest of Quebec City. Emergency workers fighting bitter cold used steam to remove ice as they searched the wreckage for victims Friday, the Toronto Star reported.
The number of dead remained uncertain. While five deaths had been confirmed, about 30 people were still unaccounted for Friday.
The Canadian Broadcasting Corp. said the home had 52 registered residents but no one was sure how many of them were on the premises when the fire began.
Veronique Hivon, the minister for social services, said the residence was not required to have a sprinkler system because it was only three stories, the Star said. She said the home was "in perfect conformity with all standards."
In an evacuation test, the home was able to get all residents out in eight minutes.