CSLB C-39 Roofing ContractorSteep-Slope RoofingHard
A roofer is preparing to install standard 5-V Crimp metal roofing panels on a residential property. What is the minimum recommended roof slope for this type of exposed fastener metal panel system to ensure proper water shedding?
- A4:12
- B1:12
- C2:12
- D3:12
Show answer & explanationAnswer & explanation
Correct answer: D. 3:12
For 5-V Crimp and similar exposed fastener metal panel systems, a minimum roof slope of 3:12 (or 3 inches of vertical rise per 12 inches of horizontal run) is generally recommended to ensure adequate water shedding and prevent water from backing up under the laps.
Why the other options are wrong
- A. 4:12 is a good slope for metal panels, but 3:12 is the minimum, so this is not the most accurate answer for 'minimum recommended'.
- B. 1:12 is typically too low for exposed fastener metal panels and risks water leakage.
- C. 2:12 might be acceptable with extra precautions and sealants, but 3:12 is the more common and safer minimum for reliable water shedding with exposed fasteners.
Metal Panel Minimum Slope
The lowest acceptable roof pitch for a specific metal roofing system, crucial for ensuring effective water drainage and preventing leaks.
- Varies by panel type (exposed vs. standing seam).
- Higher slope generally improves drainage.
- Critical for preventing water intrusion.
Memory trick: Three-twelve for V-Crimp, or water will swim.