The family was gathered at their home on north Matilija Avenue for the orthodox Christmas holiday. They were watching TV when they heard smoke alarms and found their 20-foot Christmas tree engulfed in flames.
The homeowner tried to douse the fire with a hose but it was already too late. Flames moved up to the attic, eventually destroying most of the two-story house.
"He encountered heavy heat and smoke and was unable to gain entry into the foyer because it exploded that quick," said Los Angeles Fire Battalion Chief Randy Beaty. "He was able to get his family out of the building safely."
It took 60 firefighters over an hour to put out the flames. One firefighter suffered minor injuries and is expected to be okay.
Firefighters came back to the house on Saturday to make sure the fire was out and the structure was stable for insurance adjustors.
Orthodox Christians, who use the Julian Calendar, celebrate Christmas on Jan. 6.
City News Service contributed to this story.