Neighbours were woken by the sounds of the blaze as plumes of smoke spilled out the rear of the Guildford property.
“Just the crackling noise at night I was quite fearful it sounded like fireworks,” Gabrielle Chidiac said.
“It was a bit of a shock, like ‘will it reach into our yard?'”
“On arrival, crews found the house well alight with flames starting to head towards the adjoining property,” Fire and Rescue NSW Superintendent Adam Dewberry said.
“The house is totally destroyed by the fire.”
After the blaze had been extinguished, firefighters discovered dozens of cannabis plants growing in the back shed.
Police have since dismantled the hydroponic set-up and seized the drugs, lights and growing equipment.
Meanwhile, another home on Brisbane Road, St Johns Park, also caught on fire overnight.
“It also suffered significant damage,” Superintendent Dewberry said.