A neighbour, whose comments were posted on the Henderson Volunteer Fire Brigade Facebook page, said it was really scary and she could feel the heat from inside her house.
The post said the heat was intense, even from her lounge.
"We definitely couldn't walk up the drive," it said.
"Luckily everyone got out okay, so relieved to see all the firefighter crew, or we'd be jumping the back fence to get to safety."
West Harbour Fire Brigade Chief Fire Officer Zhann Smith said it took about 25 firefighters about 30 minutes to bring the blaze under control.
West Harbour Fire Brigade Chief Fire Officer Zhann Smith said it took about 25 firefighters about 30 minutes to bring the blaze under control. Photo / West Harbour Volunteer Fire Brigade
Smith said 11 occupants were originally believed to have been in the house at the time of the fire, and one person treated for smoke inhalation.
Smith said it was a timely reminder for people to check they had working smoke alarms.
West Harbour Volunteer Fire Brigade posted on Facebook said it was "absolutely heartbreaking" to attend these types of calls.
"... but thankfully all the occupants made it out safely, with one being looked at by ambulance crews for smoke inhalation."
A fire safety officer is investigating and the cause of the fire is still to be determined.