Shortly after 14:30 today, Company 27 was alerted for a working building fire on Spigot Valley Rd (4-4 Box). Engine 4-1 (clearing brush fire) arrived and confirmed a working fire. ET27 arrived and placed a line quickly in service to contain the fire. RE27 supplied the ET. Crews had extensive overhaul on Division 2. Thank You to South Mountain ET16 for covering the Valley during the incident.