CCI Roofing & Weatherproofing Standards 3 — Questions and Answers
Question 1: Per IRC Section R905.1.1, what is the minimum slope requirement for asphalt shingles when double underlayment is not used?
- 2:12
- 3:12 (Correct answer)
- 4:12
- 5:12
Correct answer: 3:12
IRC requires a minimum 3:12 slope for standard asphalt shingle installation without the additional protection of double underlayment.
Question 2: What is the term for the upward deflection of a roof membrane or panel caused by differential air pressure between the interior and exterior of a building?
- Thermal bridging
- Wind uplift (Correct answer)
- Blistering
- Ponding
Correct answer: Wind uplift
Wind uplift occurs when wind creates a pressure differential that exerts an upward force on roof membranes or panels, potentially causing separation.
Question 3: A CCI inspector finds that modified bitumen roofing membrane laps are only 2 inches wide. What is the correct minimum lap width per industry standards?
- 3 inches
- 4 inches
- 6 inches (Correct answer)
- 8 inches
Correct answer: 6 inches
Modified bitumen membrane side laps and end laps require a minimum 6-inch overlap to ensure a watertight seal.
Question 4: Which ASTM standard governs the testing of asphalt shingles for physical properties including wind resistance?
- ASTM D226
- ASTM D3462 (Correct answer)
- ASTM D1970
- ASTM E108
Correct answer: ASTM D3462
ASTM D3462 is the standard specification for asphalt shingles made from glass felt and surfaced with mineral granules, including wind resistance testing.
Question 5: When inspecting roof drainage, what is the maximum allowable area of roof that one 4-inch diameter drain can typically serve under IPC standards?
- 1,000 sq ft
- 2,000 sq ft (Correct answer)
- 3,000 sq ft
- 4,000 sq ft
Correct answer: 2,000 sq ft
Under IPC guidelines, a single 4-inch roof drain can typically serve up to 2,000 square feet of roof area based on standard rainfall intensity calculations.
Question 6: What is the recommended minimum R-value for roof insulation in Climate Zone 5 per ASHRAE 90.1?
- R-20
- R-25
- R-30 (Correct answer)
- R-38
Correct answer: R-30
ASHRAE 90.1 recommends a minimum R-30 for roof/ceiling assemblies in Climate Zone 5 to meet energy code requirements.
Question 7: Which type of roofing membrane is installed in a single layer and relies on vulcanized rubber chemistry for its weatherproofing properties?
- TPO
- EPDM (Correct answer)
- PVC
- APP modified bitumen
Correct answer: EPDM
EPDM (Ethylene Propylene Diene Monomer) is a single-ply membrane made from vulcanized synthetic rubber, widely used in commercial low-slope roofing.
CCI Roofing & Weatherproofing Standards 3
Per IRC Section R905.1.1, what is the minimum slope requirement for asphalt shingles when double underlayment is not used?