A 30-foot wall uses studs at 16 inches on center with a stud at each end. How many layout studs are needed before openings?
Correct Answer
A) 24 studs.
Thirty feet is 360 inches. At 16 inches on center, 360 / 16 = 22.5 spaces, so round up to 23 spaces and use 24 studs including both ends.
Why This Is the Correct Answer
Thirty feet is 360 inches. At 16 inches on center, 360 / 16 = 22.5 spaces, so round up to 23 spaces and use 24 studs including both ends.
Why the Other Options Are Wrong
Option B: 22 studs.
22 studs. is below the supported result for wall framing layout; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 23 studs.
23 studs. is below the supported result for wall framing layout; it likely omits allowance, conversion, coverage, or final round-up.
Option D: 25 studs.
25 studs. is above the supported result for wall framing layout; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Wall Framing Layout cart for Laying Out: feet first, inches second, whole units last.
Reference Hint
Study anchor (closed-book): memorize Wall framing layout from California Residential Code, California Code of Regulations Title 24. / Title 24 California Residential Code wall framing layout concepts; know the rule or calculation trigger without relying on exam-room lookup.
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