Abstract: A ventilating system for a swine shelter including an air inlet device located on the prevailing wind sidewall of such shelter and an air exhaust device on the other side of such shelter. The air inlet and exhaust devices include fans controlled by timers and thermostats so as to maintain a closed-shelter, controlled-environment type of confinement system. The air inlet is located within the eave of the shelter but the air exhaust is located so as to accept air from the manure pit only. A second air inlet and air exhaust are provided for use in the non-winter months.