PIEDMONT -- A fire that gutted a sprawling Piedmont house and damaged two other homes may have started near a balcony hot tub, but investigators continue to probe Tuesday's blaze, fire officials said Friday.

Piedmont Fire Chief Bud McLaren said the fire does not appear to be suspicious.

McLaren on Friday also gave updated damage figures for the three houses.

The four-story, 4,700 square foot house at 150 Maxwelton Road where the fire started about 2:25 p.m. Tuesday sustained at least $560,000 damage, he said. The home at 140 Maxwelton had $70,000 in damage and the residence at 180 Maxwelton had $25,000 in damage.

He said the residents at 140 and 180 have returned to their homes but the residents at 150 will not be able to return for some time.

Piedmont firefighters with the help of mutual aid from Oakland had the fire under control within an hour. There were no injuries reported.