bird size, number, and heat production (Btu's/hr per lb)
lighting system details
maximum expected outside temperature
maximum desired inside temperature (typically 85 F)
Total heat gain through each building surface as well as the birds. - graphic.
Breakdown in percentages of various heat sources in the house - pic echart
Minimum tunnel fan capacity required to maintain 5 F differential betwen the pads and the fans
cfm per square foot
cfm per bird
Average air velocity obtained with minimum recommended tunnel fan capacity.
You can change the minimum required tunnel fan capacity and the spreadsheet will calculate the pad to fan temperautre difference.
It is important to note that t he spreadsheet determines the minimum amount of tunnel fan capacity required to maintain at most a 5 F temperautre difference between the inlet and fan ends of the house. Additional fan capacity is often required to increase the velocity to produce sufficient bird cooling.