EDMONTON -- An early morning fire forced residents to flee and heavily damaged an Edmonton duplex early Wednesday morning.

The fire at 77 Street and 122 Avenue was reported just after 3:30 a.m.

The Ostaszewskis, a family of six, escaped from one of the units thanks to their daughter. The 13-year-old noticed flames outside her window and woke her family.

"Everything happened so fast," said Tamara Ostaszewski through tears. "All I can keep thinking is what if she didn't wake us up? What if she didn't wake up?"

Ostaszewski said after their daughter woke them up, her husband Raven ran to wake their son and grab their two-year-old daughter.

"I grabbed our six-month-old from the crib that's beside my bed and I just ran out the door."

She says if it wasn't for their daughter, things could have turned out much differently.

"If it wasn't for her, I don't think we would have made it out," said Ostaszewski. "She's a hero."

"If she did see that and she was able to get everybody out on time without injury, no injuries, yeah absolutely she'd be a hero," said District Fire Chief Brian Hoekstra.

All 18 residents of the duplex and their pets made it out safely. Edmonton Fire Rescue Services said one man was evacuated by fire crews and assessed by EMS but was not taken to hospital.

No injuries have been reported. The Emergency Support Response Team (ESRT) provided temporary accommodations for 18 people.

The fire was declared under control before 5 a.m. and was out just after 5:30 a.m. The fire took crews nearly two hours to put out.

Fire investigators are working to determine a cause. Damages are estimated to be $350,000.

With files from CTV News Edmonton's Amanda Anderson.