When hot, cows tend to avoid areas of bright light, which can lead to more bunching in dark areas of the barn. In tunnel-ventilated barns that also have a natural ventilation option, it is more difficult to disperse light evenly. It is also easier to control light intensity in a cross-ventilated barn. This provides more evenly distributed air over a greater distance.

Whereas tunnel-ventilated barns only have inlets at the end wall or along sidewalls on one end of the barn, cross-ventilated barns have inlets along the entire length of the barn. Baffles and fans are necessary to redirect airflow, though. While tunnel ventilation works best in barns with less than six rows, cross ventilation can be used in barns up to 24 rows wide. He also explained that barns using cross ventilation can be built wider. Dougherty pointed out a benefit is that the air travels parallel to the stalls, which should give better airflow where the cows lie down. While tunnel ventilation directs airflow parallel to the feed lane, cross ventilation typically goes perpendicular to the feed lane. They use fans to pull outside air into the barn. Iowa State University Extension Ag Engineering Field Specialist Brian Dougherty compared ventilation options at a dairy design workshop held in Garnavillo, Iowa.īoth tunnel and cross ventilation are forms of mechanical ventilation.

Cross ventilation historically hasn’t been used as much, but it is growing in popularity for dairy cattle housing.

Natural ventilation and tunnel ventilation are two common options for dairy barns. Ventilation is a key component of barn design.

Odd dairy barn design