A Brisbane family has been torn apart by a housefire that killed a couple and left their 17-year-old daughter with severe burns.

The girl is in hospital in critical condition with serious burns to her face, chest, arms and airways.

Her father and stepmother died while asleep in their bed, overcome by smoke so thick firefighters had trouble getting inside the Bracken Ridge house, in north Brisbane.

Desperate screams, loud bangs and the sound of smoke alarms going off woke residents in the usually quiet cul-de-sac around 4am (AEST) on Friday.