Williston North Dakota Heating cooling criteria

robert borders

What is the design temperature in the winter for williston north dakota? here in SE Iowa [the florida of iowa] we use a budget number of 25 BTU per square foot on 2 X 6 insulated studs wood construction and 35 BTU per sq ft for 2 X 4 studded walls and 600 sq ft per ton cooling. yes, i know it is not the manual j method but it works. this works for -10 degrees at 70 degrees stat winter and 75 indoors and 95 degrees outdoor summer