A working smoke alarm is credited for alerting a sleeping Gravenhurst woman to a destructive fire at her home early Thursday morning.

The blaze broke out around 4 a.m. and the shrill sound of the smoke alarm alerted and gave the woman the critical minute she needed to escape the fire, the department said a press release.

Fire crews from Gravenhurst Stations 1 and 2 responded to the fire on Highway 11, south of Kilworthy Road. Upon their arrival, they found a fierce fire had fully enveloped a bedroom and had spread to an adjoining kitchen and dining room area.

Crews were able to prevent the fire from spreading further throughout the home.

“The heat inside the home was very intense, but crews pushed their way inside in an aggressive fire attack,” said Fire Chief Larry Brassard. “They did an absolutely wonderful job in holding the fire in its developed state, and then quickly gaining control and extinguishing the fire.”

The fire chief said there were two important factors in this fire - the first being the presence of a working smoke alarm, and the second being a simple closed door.

“The bedroom door of the room of origin was closed during the night, and it slowed the spread of the fire initially, actually containing it giving the occupant extra added time to escape,” said Brassard.

The woman managed to take her two pets with her as she fled the building. Though not injured, the woman was taken to hospital as a precaution. She is now staying with staying with relatives

The house sustained extensive fire and heat damage which is preliminarily estimated at $75,000.

The cause of the fire is still under investigation, but it is not considered suspicious.