James Poole, Raleigh fire division chief, said crews arrived at 4508 Wingate Drive around 5 a.m. The family was out of the home when crews arrived and the home's roof was engulfed.
A cause has not been determined, but investigators say the fire is the work of an arsonist. Authorities say someone set fire to the house's deck while the family was inside.
Poole told ABC11 that fire detectors probably saved the family.
Investigators will return to the scene Friday.