Investigators are working to determine what caused two early morning house fires that led to property damage and displaced seven residents in Gwinnett County.

Firefighters were first called to a fire near Buford that displaced a family of five in the 4300 block of Sardis Church Road about 1:50 a.m. Thursday, Gwinnett fire spokesman Justin Wilson said.

When crews arrived, they found the blaze had started in a wall of a single-story, wood-frame house and extended to the attic space.

Although firefighters were able to get the fire under control in less than an hour, it caused extensive damage to the attic of the home, Wilson said.

Less than two hours later, crews were called to the other fire in the 3000 block of Chandon Lane near Lawrenceville.

A sleeping couple awoke to the sound of their smoke detectors about 3:30 a.m., Wilson said.

Firefighters arrived on scene and found a two-story, wood-frame structure with heavy fire on the right side of the second floor.

The fire started in the chimney chase and quickly spread to the attic, Wilson said. The blaze caused the roof to collapse partially before crews could got the fire under control at 4:35 a.m.

In both fires, crews initially used attack hose lines to fight the blazes from inside the homes. With bitter cold continuing to grip metro Atlanta and much of the country, water froze on the sidewalk and street in front of the Chandon Lane residence.

“With the intense blaze, firefighters were forced to transition to a defensive fire attack,” Wilson said.

Multiple hose lines and one aerial apparatus were used to bring the fires under control, according to officials.

Although no injuries were reported, officials used the incidents as opportunities to remind people of fire safety strategies.

“Be sure to install working smoke alarms on every level of the home and in each bedroom,” Wilson said. “Develop a home escape plan, and practice fire drills regularly.”

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