At 1615 hours Box 1-2 sent the Squad, Wagon 4, Towers 1,2, and Chief 4 to 1221 N. 14th Street for a kitchen fire. Reported as a grease fire with smoke and flames visible. Wagon 4 arrived with heavy smoke showing from a 3 story, occupied, duplex. Interior crews reported heavy fire on the first floor. Chief 4 requested the balance of the box. Two lines were stretched and made a good knock on the fire with some extension to the second floor. A precautionary 3rd line was stretched into the exposure building. Companies were about 2 hours befire going in service.