2015 MN Rules 1309.0602, subp. 1. This is the prescriptive table for wall studs in tall walls. Footnote d provides a new method for determining the number of studs required on each side of an opening when openings occur in a tall wall. The footnote reads: “Where studs do not extend full height due to a wall opening, full height studs shall be provided on each side of the opening, equal in number to the spacing of the required full height studs multiplied by half the width of the opening, plus one stud.”

This is a classic example of a sixth grade math problem where the teacher gives you a narrative and requires that you develop a formula to solve a problem.

The text can be written as a formula which can be used to provide the answer to how many studs are required on each side of an opening. Based on the text in the footnote, the formula would go like this: N (number of full height studs each side of opening) = S (spacing of the required full height studs) X W (width of the opening) ÷ 2 (half the width) + 1 (add one stud).

The spacing of the required full height studs as shown in the table is 24”, 16”, 12”, or 8”. Let’s assume we are using 16” o.c. spacing so S will be 16. The rule is silent on whether the width of the opening is in feet, inches, or cubits but let’s guess that it is in feet and that the opening is 4 feet wide so W will be 4.

So the formula would be: N = 16 X (4 ÷ 2) + 1. In this example, assuming that the opening is supposed to be measured in feet and not inches, the number of studs on each side of the opening would be 33. If the width of the opening were to be measured in inches, then the number of studs on each side of the opening would be 385. Is the correct answer 33 or 385 studs on each side of the opening? Do you believe 33 studs to be sufficient on each side of the opening? Does anyone know what a cubit is?