A suspicious fire in Jackson Circuit, Albanvale, occurred early on Thursday morning.
Fire Rescue Victoria (FRV) crews responded to the house fire about 4.30am, following multiple calls to triple-0.
A total of 22 firefighters arrived to find two cars on fire in a driveway with flames spreading to the single storey, brick veneer dwelling.
Wearing breathing apparatus, firefighters worked to extinguish the fire with firefighting efforts hampered by a collapsed roof.
The incident was declared under control after 50 minutes.
All occupants, a family of four, evacuated from the home with brigade assistance, and were assessed by Ambulance Victoria for symptoms of smoke inhalation.
Zero injuries have been reported.
Victoria Police and Ambulance Victoria were on scene to support firefighting activities.
Firefighters will remain on scene for some time, to ensure the fire is fully extinguished.
An advice message has been issued for smoke in the area.
