Limuru Sub County Administration Police Superintendent Moses Opiyo says no one was hurt in the fire which started at 11am.
Opiyo said investigations have been initiated to determine the cause of the fire.
Factory workers told Capital FM News that the fire started at the basement where raw materials are usually stored.
Staff were evacuated from the facility as Limuru town residents rushed to help to put out the fire. They were later joined by the Nairobi City County Fire Brigade.
By the time the Capital FM News was leaving the facility at around 3pm, staff and factory security personnel were in the process of salvaging property and materials which had not been destroyed.
Administration Police officers cordoned the entrance of the facility to keep members of the public away.