A working smoke detector is being credited for alerting a resident to a fire at a home in Ancaster.

Crews were called to the Church St. home around 8:30 a.m. Monday for a structure fire.

A woman who was in the house at the time heard the smoke alarm go off and was able to get out safely.

Officials say it was an attic fire that likely started in a bathroom exhaust fan. The cause was likely electrical.

Crews remained on scene putting out hot spots for a few hours.