A balcony waterproofing detail requires 1/4 inch slope per foot away from the building. What fall is needed over 10 feet?
Correct Answer
B) 2.5 inches.
A quarter inch per foot over 10 feet requires 2.5 inches of fall.
Why This Is the Correct Answer
A quarter inch per foot over 10 feet requires 2.5 inches of fall.
Why the Other Options Are Wrong
Option A: 1.25 inches.
1.25 inches. is below the supported result for waterproofing slope calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 5 inches.
5 inches. is above the supported result for waterproofing slope calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 10 inches.
10 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 quarter, adjust for inch, then let Checking Exterior 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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