The fire caused major damage to the one-story, 5,225-square-foot home at 80 Mount Vernon Lane in Atherton, authorities said.
The couple residing there awoke to a popping sound, smelled smoke, went outside, saw smoke rising and called 911 at 2:55 a.m., Chief Schapelhouman of the Menlo Park Fire Protection District said in a phone interview. The couple was uninjured but their two cats succumbed, probably to smoke inhalation, the chief said.
The fire destroyed about 75 percent of the attic, part of which collapsed — an indication that the fire got a good start before being detected, he said. The fire may have started in a closet on the first floor, he noted.
The house was in the final weeks of a remodel, but the fire has left it uninhabitable, the chief said.
A second alarm went out at 3:19 a.m. and firefighters had the fire under control at 3:33 a.m., Chief Schapelhouman said.
Having soaked the attic, firefighters quickly began a salvage operation of personal goods to avoid damage due to falling wet sheet rock, he said.
An initial estimate put the damage to the structure and personal belongings at $350,000, he said. Building officials with the town will be called in to further evaluate the damage to the house, Chief Schapelhouman said.
The fire district will investigate why the smoke detectors, which are powered by batteries, did not work.
When they arrived, firefighters had to break through the electrically powered front gate. The investigation will include why the gate malfunctioned, the chief said.
A detached garage of 1,000 square feet was not damaged, nor was there any significant damage to trees or other vegetation, Chief Schapelhouman said.