DRACUT — A four-alarm fire caused major damage to a home at 215 Varnum Road overnight.

The lone occupant, a 76-year-old woman, escaped without injury. Elaine Buote heard the alarm and went out into the driveway with one of her dogs, said her daughter, Donna Buote.

The first call for the fire arrived just before 4:15 a.m. Firefighters from several communities, including Lowell and Tyngsboro, responded when the call reached multiple alarms.

A passerby saw Elaine Buote outside and stopped. He called for help and went inside the burning home to rescue a second dog trapped in the bedroom, Donna Buote said.

The family home was built by Donna Buote’s grandfather. She stopped at the site mid-morning to see if she could save a family photo. Her mother will stay with her.

The home was built in 1949, according to town assessor records.

(This story will be updated throughout the day.)