STAMFORD - Building officials say that the Stamford home that caught fire on Christmas Day and left five people dead was lacking building inspections and a wired smoke detector system.

Officials say that most of the second floor, excluding the master bedroom, hadn't been inspected and lacked a certificate of approval for habitation.

The home's wired smoke detector system was also not operational at the time of the fire and authorities say they aren't sure if any battery-operated smoke detectors had been installed for the time being.

The medical examiner has reported that all five victims of the fire had died from smoke inhalation.

Assistant Stamford Fire Chief Peter Brown says had the smoke detectors been operational, it could have given the family a chance to escape the smoke and fire.

The fire started because of smoldering fireplace embers left in the mud room, according to fire investigators.

Officials say that the home had been undergoing renovations and the original method of construction, called balloon construction, left the walls hollow and may have led the fire to spread many times quicker than with modern construction techniques.

Firefighters receive special counseling after Stamford fireStamford house torn down after 5 die in fire5 killed in Christmas morning house fire