Firefighters spent the afternoon cleaning up rubble at the home where two families lived.
The fire broke around 11 a.m in the 900 block of S. 17th Street.
No one was hurt in the fire, but firefighters arrived to find flames shooting from the structure.
"No such thing as a routine fire,"said Jason Ziph, the St. Joseph Fire Inspector. "Smoke and flames were showing so our guys went to work," said Ziph.
The cause of fire is still under investigation.
Donations for the family are being accepted.
Contact the Red Cross if you can help.