This from Art Zern:

Sycamore Engines 1 and 2 responded to an activated fire alarm at Menards (1825 Mercantile Dr) Monday morning at 0224.  While enroute, PD arrived and reported heavy smoke on the A side.  Engine 1 requested a BOX while enroute.  Engine 1 arrived with heavy smoke showing (the store was full, floor to ceiling), conducted a size-up and gathered intel from PD units on the scene.  E-1 pulled a 2 ½”, located and extinguished the fire in the electrical section.  DeKalb T-1 provided vertical vent via skylights and the sprinkler system was supplied. Extensive overhaul and smoke removal started with the assistance of mutual aid companies and  MABAS Div. 8 mobile Ventilation Unit was special called.

Excerpts from the daily-chronicle.com:

The Sycamore Fire Department responded to a call at 2:22 a.m. Monday at the big-box store at 1825 Mercantile Drive,. Firefighters were able to control the flames within 15 minutes. The fire looks to have started on a display shelf near the front of the store, although the cause has not yet been determined.

Sycamore Fire Chief Pete Polarek said the fire originated in the lighting department to the left of the main entry door to the store. “The fire consumed an area approimately 10 feet by 6 feet,” he said. “The flame height was probably in the area of 15 feet or so.”

Estimated damage currently is at $500,000 because of different factors at play such as cleaning costs, the loss of merchandise, and the loss of business.

Firefighters stayed at the store for 2½ hours in order to overhaul, ventilate and investigate.

Eleven fire companies responded including: Sycamore, DeKalb, Cortland, Genoa-Kingston, Sugar Grove, Elburn, Kirkland, St. Charles, Burlington, Malta, Pingree Grove, the MABAS Division 8 Mobile Ventilation Unit, Sycamore Public Works, and the Sycamore Police Department.??