Fire Capt. Chuck Rangel said PG&E crews investigating a report of a power outage saw smoke coming from a home at 3993 Forestwood Drive and called 911 at about 12:20 p.m.
Firefighters arrived and found a fire burning inside the home's walls.
Rangel said the blaze started near the spot where electrical power is routed into the residence. He said it appears the home was being used to cultivate marijuana.
The fire was controlled just before 1 p.m. No one was home when the fire started and no injuries were reported.