The bracing plan reproduces the minimum braced wall panel length values for the continuous sheathing method at this 10-foot wall height: where the tallest adjacent clear opening is 64 inches the minimum panel length is 24 inches; at 80 inches it is 30 inches; at 96 inches it is 36 inches; and at 120 inches it is 48 inches. Beside the segment you are measuring, the tallest adjacent clear opening is a 96-inch door, and the segment itself measures 32 inches. Does the segment qualify?
- AYes; 32 inches exceeds the 30-inch minimum the table gives for a segment beside an opening of that size
Thirty inches is a value in the table, but not the one that applies beside a 96-inch opening. Reading down the wrong column gives a minimum short enough to make the segment pass by 2 inches when it actually fails by 4.
- BYes; 32 inches exceeds the 24-inch minimum length the table gives for a wall of this height
Wall height is only one of the two entries into the table, and the width of the adjacent opening is the other. Picking the minimum by height alone ignores the variable that actually governs this segment.
- No; with a 96-inch adjacent opening the segment must be at least 36 inches, so it is 4 inches short
- DNo; a 10-foot wall always takes the longest value in the table, so a 48-inch segment is required at this opening
The table is not read by taking the worst case. Each combination of wall height and opening width has its own minimum, and defaulting to the largest asks the builder for a foot of wall the code does not require.
Why C is correct
The governing input is the tallest adjacent clear opening height, 96 inches, which the table pairs with a 36-inch minimum panel length at this wall height. A 32-inch segment falls short by 4 inches and cannot be counted as bracing.
What this question is testing
Whether the candidate can select the correct row of a two-variable table using the adjacent opening height rather than the wall height alone, and whether the candidate rejects both the too-generous and the too-conservative reading.
On the job
This is the detail that separates continuous sheathing from ordinary bracing on the job. Narrow segments between a door and a window are exactly where the method is being used, and the framer sizes them by eye. Inspectors measure the segment and the adjacent opening at the same time, because either number alone tells you nothing, and they mark qualifying segments on the plan as they go.
Memory technique
Taller opening beside it, longer panel required.
Exam tip
In continuous sheathing tables, the tall opening next door is what sets your minimum panel length.
Where to look it up
IRC Chapter 6 wall bracing, minimum length of braced wall panels for continuously sheathed methods.