Police Capt. Richard Conklin said unanswered questions remain, although authorities have determined that embers in a bag of discarded fireplace ashes caused the Dec. 25 house fire. For example, officials want to know if there were smoke alarms, the status of renovation work in the house and whether the contractor had permits, he said.
Advertising executive Madonna Badger, the home's owner, and Michael Borcina, a friend and contractor working on the house, escaped the fire.
Badger's parents, Lomer and Pauline Johnson, who were visiting for the holiday, and Badger's two children - 10-year-old Lily and 7-year-old twins Grace and Sarah - died of smoke inhalation. Lomer Johnson also suffered a blunt head and neck trauma, which resulted from a fall or being hit by an object.
The issue of permits could figure in the investigation because the Connecticut Department of Consumer Protection has said that neither Borcina nor his company, Tiberias Construction Inc., was registered to perform home improvement work in Connecticut.
Contractors are required to register with the state, though numerous building and other permits are issued by local officials.
The agency said it did not yet have enough information about what work may have been done or completed and would not comment on whether it will investigate.
"We believe that it is too early to speculate on the specifics of the home improvement work that has been described in media reports," consumer protection agency spokeswoman Claudette Carveth said in an email Wednesday. "We believe that it is appropriate now to allow friends and family to grieve for the tragic losses they have experienced. We will address the pertinent regulatory issues in due course."
Borcina does not have a listed phone number and could not be reached for comment.
Stamford authorities deemed the house unsafe following the fire and ordered it torn down the day after the fire.
Conklin said the fire can be used to teach authorities and the general public about how to prevent similar tragedies.
"This is a learning situation," he said. "We want answers. It's logical we assist."
Stamford fire Chief Antonio Conte said the fire was Stamford's deadliest since a 1987 blaze that also killed five people.
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