The rear wall runs 24 feet, jogs back 3 feet, then continues another 14 feet, and the approved plan designates all of it as one braced wall line requiring bracing equal to 25 percent of the braced wall line length. What length of bracing is required?
- 9 feet 6 inches
- B10 feet 3 inches
This comes from adding the 3-foot jog into the line length for a total of 41 feet. The jog runs perpendicular to the line and is an offset, not a length along it.
- C6 feet 0 inches
This treats only the 24-foot run as the braced wall line and discards the 14-foot run beyond the jog, even though the plan designates the whole rear wall as a single line.
- D7 feet 7 inches
This applies 20 percent to the correct 38-foot length. The plan requires 25 percent, and using a percentage from a different table row is the usual source of the error.
Why A is correct
The braced wall line length is measured along the line, so the two in-line runs of 24 feet and 14 feet give 38 feet, and the 3-foot perpendicular jog adds nothing. Twenty-five percent of 38 feet is 9.5 feet, or 9 feet 6 inches of required bracing.
What this question is testing
Whether the candidate can measure a braced wall line correctly when the wall is offset, applies the percentage from the approved plan rather than a remembered one, and converts a decimal foot result into feet and inches.
On the job
Houses jog. Bays, chimney chases and offset garages all interrupt an exterior wall, and the first decision an inspector makes is whether the plan treats the offset segments as one braced wall line or two. That decision lives on the bracing plan and it changes both the required length and where panels may go. Measuring is done with a long tape along the designated line, ignoring the depth of any offset within the permitted distance.
Memory technique
Jogs move panels sideways; they do not make the line longer.
Exam tip
Braced wall line length is measured along the line, not around the jogs.
Where to look it up
IRC Chapter 6, wall bracing, braced wall line definitions and the permitted offset of panels from the line.