A mother and her two children woke to find themselves trapped in a bedroom as fire ripped through their home.
The terrified family was rescued by firefighters called to the blaze in Teasel Close, Broadfield, Crawley.
The woman, her 14-year-old daughter and her two-year-old son were stranded in a rear first-floor bedroom.
As firefighters raced to the scene the family was given survival advice over the phone by a fire control operator.
When fire crews arrived they had to use a ladder to reach the distraught family who were taken to Crawley Hospital to be treated for the effects of smoke but a spokesman for West Sussex Fire Brigade said it could have been a lot worse.
He said: "The property was fitted with a smoke alarm but it didn't have a battery.
"The occupiers are extremely lucky to have been rescued from the property alive.
"We would advise all householders to fit at least one smoke alarm in their property.
"Further advice can be sought from their nearest fire station."
Three fire engines from Crawley were sent to the blaze, which was brought under control within five minutes.
Part of the house was severely damaged by fire and the rest by heat and smoke.
Leading firefighter Terry Moring, said: "There was severe damage on the ground floor although the fire was quite small.
"It had engulfed the ground floor landing and had gone up the stairs. The house was very heavily smoke damaged."
A joint investigation between the police and the fire brigade was under way today to establish the cause of the blaze.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article