Boston firefighters responded at 1:25 a.m. to 10 Hazelmere Rd. in Roslindale for a fire that went to two alarms before being knocked down.
The home's three residents were already outside when firefighters arrived to battle the blaze, sparked by a short circuit in the second-floor ceiling.
The Boston Fire Department estimates damage at $500,000. One firefighter was transported to the hospital for heat exhaustion.