Earlier this year, Ventilation Specialist Dan Veeneman wrote this great article on the two pillars of barn ventilation and why they matter to you.
If you ask around, most dairy farms have some sort of ventilation system in their barn. These systems will vary from region to region and farm to farm. For some, it could be a simple naturally ventilated barn with sidewall curtains that allows the natural breeze into the facility. There may not be a single fan in the barn.
For others, it could be a large, low-profile, cross-ventilated facility with a sidewall full of large exhaust fans that run continuously for months on end. Though these two concepts look completely different, both of these producers are relying on some sort of ventilation strategy to perform two crucial functions in their barn. The two pillars of any good ventilation system are air speed and air exchange.