It was one of several fires which broke out in Cork during the day.
The woman, who is in her 80s, was asleep in an upstairs bedroom of the farmhouse, about 5km outside Skibbereen, when the smoke alarm went off at about 5am.
She rushed out of the house, at Tooreenasillane on the Drinagh Road, and woke her daughter who lives next door. Together they raised the alarm.
Two dogs that also escaped went back in to the burning building and died.
The elderly woman suffered slight smoke inhalation and was treated at the scene with oxygen. She was taken to Bantry General Hospital as a precaution where her condition was described last night as comfortable.
Gardaí believe the blaze started after a piece of equipment fell from the back of a lighting stove.
The fire spread into the living-room and badly damaged the house.
Superintendent Pat Maher said he was in no doubt the smoke alarm saved the woman’s life.
Fire crews in west Cork also spent several hours tackling a gorse fire in Toormore, just outside Schull. The blaze was finally brought under control at about 3.30am.
In Cork city, up to 20 firefighters spent more than three hours fighting a blaze in an unoccupied building on the grounds of Our Lady’s Hospital, above the Lee Road in Shanakiel.
It was the sixth time in recent weeks that a fire has broken out on the site.
The alarm was raised just after 9am when flames were spotted coming from the roof of the substantial two-storey building, Teach Bríd, located some distance away from the main hospital.
The building, which is owned by the Health Service Executive, had been used for hospital staff accommodation in the past, but it has been boarded up for several years.
Five units of the fire brigade rushed to the scene but had difficulty accessing the site because of overgrown bushes and dumped rubbish.
The fire was well alight around the first floor area when firefighters arrived.
Strong winds fanned the flames and made the operation difficult.
A hydraulic water cannon platform was used to douse the flames from above but the winds reignited the blaze several times.
Despite the problems, firefighters managed to contain the blaze to the far left section of the building. There were no injuries.
Gardaí examined the scene and said the building was often used by youths as a drinking venue.
There were signs of burned papers inside and of forced access towards the rear of the building.