What Is Tunnel Ventilation?
Tunnel ventilation gets its name because in this type of system the poultry house is converted into something like a wind tunnel. In a tunnel ventilation system, all exhaust fans are placed at one end of the house and all air inlets at the other end. Ventilating air is drawn uniformly through the length of the house at a velocity of at least 350 to 400 feet per minute (4 to 4.5 mph). This high-velocity airflow through the house provides significant cooling for the birds. Evaporative cooling can provide additional protection against birds’ overheating. Tunnel ventilation is a warm-weather system. Introducing all ventilating air at one end of the house can cause chill stress on birds in cold weather. During hot weather, larger birds conditioned to tunnel house temperatures will suffer heat stress if power fails even if the house is immediately opened up. For this reason, a back-up generator is essential. Tunnel houses are usually designed to operate at static pressures ranging from 0.06
