Two housemates have jumped from their burning home in Sydney’s north-west just moments before the roof caved in.

The split-second decision saved their lives but the fire sparked warnings from authorities for residents to double-check their smoke alarms

Explosions were heard as the home was consumed by flames.

When fire crews arrived on Cameron Avenue after a fire started about 10.30pm, the residents, two housemates, were still unaccounted for.

Joe and Fua can be seen seen on CCTV running from the home after jumping from a second-storey bedroom window.

Joe said he woke up unable to breathe and called his friend.

“When I got up, I couldn’t see anything at all. It was dark, and he just got me, and threw me out the through the window,” Fua said.

Fellow housemate Sumit had lit the downstairs log fire before heading into the city as Joe and Fua slept.

He said he closed it properly and it was burning normally.

Investigators are still trying to determine if working smoke alarms were installed.

Fire and Rescue NSW Commissioner Jeremy Fewtrell wasted no time reinforcing the importance of fire safety on the first day of winter.

“Check your smoke alarms, press the button, make sure you hear the beep, if it doesn’t beep you can replace it or put a new battery in it,” he said.

Emergency Services Minister Johad Dib said there were more than 1000 house fires last winter.

“Sadly 44 per cent of those did not have a working smoke alarm and tragically 12 lives were lost,” he said.