UGA Poultry Housing

Did you know there are universal meteorological rules that dictate which combinations of outside temperature and relative humidity are possible? For instance, it is virtually impossible anywhere in the world for outdoor relative humidity to exceed 85% when temperatures are above 84°F. The chart below illustrates what combinations of outdoor temperature and relative humidity that simply don't exist in nature.

Let the arguing begin :)

Adding extra evaporative cooling pad area to a house will not tend to significantly increase the amount of cooling produced by a pad system. The chart below illustrates the change in incoming temperature and humidity on a fairly hot day if a house's pad area was increased 30% over the standard recommend pad area.

A tunnel-ventilated chicken fortress 😃

Though it may be tempting to install a larger motor pulley on a fan to increase its air moving capacity, it can prove very costly. Below is a table illusratring how increasing motor pulley size (in this case on a 54" ACME) will dramatically increase the fan's power usage and risk its motor failing.

Something to consider when deciding on a pad set temperature...the sooner you turn them on, the higher the house RH will tend to be. The charts below are based on seven years of historical weather data for a farily hot, humid chicken growing location, Dothan Alabama (Yes... I know it's more hot and humid where you are located :) ).

The charts illustrate the average number of hours per year what the incoming air temperature/RH will be for a poultry house using evaporative cooling pads where they to be set to operate at 80 F.

Keep in mind that poultry houses tend to run at least 2°F warmer than the outside air. This means cooling pads activate when the outdoor temperature hits roughly 78°F. However, in most poultry-producing regions, temperature and humidity hit a cross-over point at 80°F and 80% relative humidity (RH). When outdoor temperatures drop below 80°F, humidity rises above 80%. Running cooling pads during these times brings moisture-saturated air into a house.