It happened around 2 a.m. Friday at a duplex in the 4100 block of Arckelton Drive, behind Crabtree Valley Mall.
Flames were shooting through the roof when fire crews arrived. It took about 45 firefighters almost an hour to get the blaze under control.
Officials said everyone inside the homes got out safely and no injuries were reported.
According to the fire report, the blaze destroyed over 75 percent of the duplex. It also said an "improperly discarded smoking material" caused the blaze.
The Red Cross is currently helping the displaced residents.