Other / Not Specified, Other Business Portage, MI – Sprinkler system helps contain attic fire at business October 17, 2016 viking210 Portage firefighters put out an attic fire at a West Michigan business on Sunday. Firefighters were sent to J. Rettenmaier, 1615 Vanderbilt Ave., just before 2:30 p.m. after a fire alarm was set off at the business. According to firefighters there was light smoke coming from the building when they arrived and found an activated sprinkler. The firefighters said there was a small fire in the attic and they had to cut two holes in the roof to get to the area. No injuries were reported and the cause of the fire is under investigation by the Fire Marshal.