Fresh air is introduced to the broiler barn through fresh air inlets or flues. Air inlets can be installed in the wall, in the ceiling (duct leading outside) or they can be molded directly in the precast concrete element. With a little air intake opening, fresh air will be provided without draft, whereas with inlet open wide, the cooling will be more effective. Most often, the outgoing air is directed through exhaust air chimneys located on the roof. The ventilation can be adjusted and the cooling effect boosted with giant tunnel fans attached to the end wall. These fans, which are in particular designed for special circumstances, are quiet-running and effective.