A fire in a commercial storage facility on south Santa Rosa Avenue caused major damage Thursday to the contents inside one unit and part of the metal building.

The blaze was reported about 3:15 p.m. by neighboring business owners who saw smoke coming from the storage complex, in the 4300 block of Santa Rosa Avenue.

Firefighters from Santa Rosa, Rincon Valley and Rohnert Park took about 20 minutes to contain the fire, which torched materials and scarred a moving van inside a unit leased by North Bay Insulation.

No one was in the unit at the time of the fire and a cause was not immediately known, said Santa Rosa Fire Battalion Chief Jack Piccinini.

Firefighters cut a hole in the unit's roof to release some of the pent-up smoke and douse the blaze from above.

Piccinini estimated damage to the unit and contents at up to $50,000.

Nearby units suffered minor damage, including roof and smoke damage.

Ed Keith, who leases an adjoining unit for his company, North Bay Environmental, said the firm's files were safe but that "soot is on everything."

About 25 firefighters responded to the blaze.

You can reach Staff Writer Brett Wilkison at 521-5295 or brett.wilkison@pressdemocrat.com.

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