Faulty electrical wiring to a roof light caused a Healdsburg High School gymnasium fire early Tuesday, said Healdsburg Fire Chief Steve Adams.

The fire caused minor to moderate damage to one corner of the gym’s attic and roof, estimated at $100,000, Adams said.

School was open, but classes slated for the gym were relocated.

“It’s business as usual except being able to use the gym,” Principal Chris Vanden Heuvel said. “I was relieved when I got here and saw the damage. It was smaller than I thought.”

The firefighting response to the fire was major.

Because of the size and height of the school’s main gym, fire officials called for a second alarm, bringing a total of about 30 firefighters as Santa Rosa, Rincon Valley, Windsor and Cal Fire joined Healdsburg, Geyserville and Cloverdale firefighters.

The fire apparently burned slowly for some time before it got hot enough to activate two smoke detectors. That started a fire alarm notification to the alarm company that went to emergency dispatchers at 2:52 a.m.

The school was lucky, Adams said. Without the smoke detectors, the fire could have gone unnoticed for a few more hours and caused significant damage.

“We contained it to the northeast corner of the gym, mainly on the outside. We had to cut a few holes on the inner portion of the building,” said Ruben Mandujano, engineer and inspector for Healdsburg Fire Department.

You can reach Staff Writer Randi Rossmann at 521-5412 or randi.rossmann@pressdemocrat.com.

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