A terrified mum had to rescue her child after a fire started by her ex-partner fractured a pipe supplying gas to their home.
Stephen Dixon set a recycling bin alight outside his former family home in the early hours of the morning while his former partner and children were asleep inside.
Newcastle Crown Court heard the flames spread from the bin to the victim's car and ruptured a gas pipe leading to the house, which started to leak.
By "fluke", a passing neighbour, who had finished work early, saw the blaze and banged on the door at the property at Windermere Avenue, Easington Lane, to wake the family.
The court heard the terrified mum was unable to leave through an extension door as it was too hot but got out via the front.
Only then she realised one of her children had not come out of the house and was still upstairs, so had to run back into the property to rescue her.
A passing taxi driver also stopped to help and phoned for the emergency services.
Dixon, of Tay Street, Easington Lane, denied arson being reckless to whether life was endangered but was found guilty by a jury after a trial.
The 33-year-old has now been jailed for seven years.
Miss recorder Rachael Harrison said it was a "complete fluke" that the neighbour walked past at that time in the morning and the family were able to get out before the flames spread further.
The judge said: "This could not be, in any way, said to be minor, considering the risk that was created and potential consequences.
"It was simply good fortune a neighbour and taxi driver came along.
"What would happen had they not come along does not bear thinking about."
The judge said she accepted Dixon was a hard working family man and very "hands-on" father.
But the judge told him: "You were utterly reckless as to whether the lives of those you say you hold dear were in danger."
The judge said the mum had to "go back inside and upstairs to rescue her child" when she realised she had not come out.
The court heard after the couple's relationship had broken down in 2015 there had been a number of arguments and Dixon had sent his ex a text threatening to "burn her house and car".
On the day before he sparked the blaze, Dixon had gone to work then drank around ten bottles of beer when he finished.
Two wheelie bins were destroyed in the blaze, which was started just before 4am and quickly spread to the car and gas pipe.
The neighbour who spotted the flames had tried to move the car away from the house but was unsuccessful.
Dixon was arrested and continues to deny responsibility, despite the jury's verdict.
Nicholas Lane, defending, said Dixon turned to alcohol and other substances to cope with the breakdown of his relationship.
Mr Lane said Dixon has used his time in custody to complete courses in a bid to better himself for when he is released.