A YOUNG man allegedly killed himself and his parents by setting a home on fire, with neighbours saying they heard a woman scream as the house burned.

Two onlookers tried to help the Brisbane home's occupants, but were beaten back by flames that reached four storeys into the air.

Locals said they heard a loud explosion and could smell fuel as the fire took hold around dawn on Tuesday.

Police suspect the deaths were a double murder-suicide and resulted from a domestic dispute between drug-addicted Dylan Thomson, 24, and his parents Graeme and Ros, the Courier Mail reports.

Emergency services responded to call in Everton Hills at around 5.30pm and found a house "engulfed in flames", said Queensland Police. The bodies of two men and a woman were removed from the home and a crime scene was established.

Police are now conducting further investigations and called on the public to get in touch if they saw anything unusual in the 24 hours leading up to the crime or had dash-cam footage if they were driving in the area.

Dylan and his mother lived in the rented house and Graeme, a 53-year-old State Emergency Service volunteer, had recently travelled to Brisbane from the Whitsundays to try to reconnect after he and Ros separated a decade ago, according to the Courier Mail.

One of Dylan's workmates told officers the 24-year-old had struggled with drug addiction but had started to turn his life around.

Rowena Ostrofski told the Brisbane Times she heard the sound of something heavy being dropped on the ground, making the floor vibrate.

"I hear glass breaking so I went to the kitchen," she said. "Then I hear a woman's voice saying 'help, help' and then I look at the bigger window and I saw the smoke on the roof."

Detective Acting Inspector Joe Zitny said the house had been "significantly damaged" and there had been "barriers" to officers trying to search the home, with the bodies extracted on Tuesday night.

He said it could take around two or three days to search the area.

Homicide officers are assisting the investigation and have been speaking with neighbours.

There was nothing to suggest the residents who lived at the house were "known adversely within the street", police said.

Post-mortem examinations were due to take place on Wednesday.

- With AAP