Travis Jordan wrote:
Kevin G wrote:
I'm guessing there is a formula to be used when

I ran your numbers through the calculator (assuming no windows but
including a 24 x 8 metal R-5 door) and came up with a heat loss of about
6600 BTU / 10 degrees. So if you want the inside temperature to be 70
and the outdoor temp is zero, you would need 46K BTU. Run the numbers
for yourself and see what you get.