A balcony surface must slope 2 percent over 12 feet. What fall is required?
Correct Answer
D) 2.88 inches.
Two percent of 12 feet is 0.24 feet. Converting to inches gives 2.88 inches.
Why This Is the Correct Answer
Two percent of 12 feet is 0.24 feet. Converting to inches gives 2.88 inches.
Why the Other Options Are Wrong
Option A: 1.44 inches.
1.44 inches. is below the supported result for waterproofing slope calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option B: 2.40 inches.
2.40 inches. is below the supported result for waterproofing slope calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 3.20 inches.
3.20 inches. is above the supported result for waterproofing slope calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Measure to percent, adjust for feet, then let Checking Balcony set the finish line.
Reference Hint
Study anchor (closed-book): memorize Waterproofing slope calculation from California Building Code, California Code of Regulations Title 24. / Title 24 California Building Code exterior walking surface drainage concepts; know the rule or calculation trigger without relying on exam-room lookup.
More Class B Trade Questions
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