Louisiana 7-803 Residential Roofing Exam
Questions and Answers | 2026/2027 Edition |
Verified Questions & Correct Answers | State
Licensing Examination Preparation | Grade A
Guaranteed Study Guide
SECTION 1: ROOFING MATERIALS & FASTENERS
(Louisiana Gulf Coast Corrosion & Wind Resistance Emphasis)
Q1: When selecting fasteners for roofing installation in a home located within 3 miles of
the Louisiana Gulf Coast, what is the minimum corrosion resistance requirement per
IRC Section R905.1.1?
A. Galvanized with G-60 coating
B. Electro-galvanized finish
C. Hot-dipped galvanized with G-90 coating
D. Standard zinc-plated nails
Correct Answer: C
Rationale:
● ✅ C is correct: IRC Section R905.1.1 requires corrosion-resistant fasteners. For
coastal Louisiana within 3 miles of salt water, G-90 hot-dipped galvanized is the
minimum standard due to accelerated corrosion from salt air and high humidity.
This provides approximately 0.90 oz/ft² of zinc coating.
, ● ❌ A is wrong: G-60 coating (0.60 oz/ft²) provides insufficient protection for
❌ B is wrong: Electro-galvanized fasteners have thinner zinc coating (typically
coastal Louisiana's salt-laden environment and will corrode prematurely.
●
0.2-0.4 oz/ft²) applied electrolytically, creating less bond strength and failing
❌
within months in high-humidity coastal conditions.
● D is wrong: Standard zinc-plated nails lack sufficient corrosion resistance for
exterior roofing applications and will fail rapidly in Louisiana's humid subtropical
climate.
Q2: For asphalt shingles installed in Louisiana Wind Zone 2 (130+ mph design wind
speed), what is the minimum ASTM wind resistance rating required?
A. ASTM D3161, Class F (110 mph)
B. ASTM D3161, Class G (120 mph)
C. ASTM D7158, Class H (150 mph)
D. ASTM D3018, Type I only
Correct Answer: C
Rationale:
● ✅ C is correct: Louisiana Wind Zone 2 (southern parishes) requires ASTM
D7158 Class H (150 mph) or ASTM D3161 Class F (110 mph) with enhanced
fastening. However, most jurisdictions now require D7158 Class H for
❌
high-velocity hurricane zones to meet IRC R905.1.1 and LSUCC amendments.
● A is wrong: Class F (110 mph) is insufficient for Zone 2; adequate only for
❌
Wind Zone 1 (northern Louisiana, 90-110 mph).
● B is wrong: Class G (120 mph) does not exist in ASTM D3161; ratings are
❌
Class A (60 mph), D (90 mph), F (110 mph).
● D is wrong: ASTM D3018 is the standard specification for Class A, B, C fire
ratings, not wind resistance.
Q3: What is the minimum thickness requirement for roof sheathing (decking) in new
residential construction under the Louisiana State Uniform Construction Code?
, A. 3/8 inch plywood or OSB
B. 7/16 inch OSB with APA span rating 24/16
C. 15/32 inch (1/2 inch nominal) plywood or OSB
D. 5/8 inch plywood only
Correct Answer: C
Rationale:
● ✅ C is correct: IRC Table R503.1 requires minimum 15/32-inch (nominal 1/2
inch) plywood or OSB for roof sheathing when supports are spaced 16 inches on
❌
center. Louisiana amendments enforce this strictly due to wind uplift concerns.
● A is wrong: 3/8 inch is prohibited for roof sheathing under IRC; insufficient
❌
strength for wind loads.
● B is wrong: 7/16 inch OSB is permitted only for wall sheathing (24-inch o.c.
studs) or roof sheathing with 24-inch o.c. rafters in some jurisdictions, but 15/32
❌
inch is the safer, code-compliant minimum for standard roofing.
● D is wrong: 5/8 inch provides superior performance but is not the code
minimum; 15/32 inch is acceptable when properly installed.
Q4: In coastal Louisiana, what type of underlayment is required beneath asphalt
shingles on roof slopes between 2:12 and 4:12?
A. Single layer of 15-pound felt
B. Double layer of 15-pound felt with 19-inch headlap
C. Single layer of synthetic underlayment only
D. Self-adhering polymer-modified bitumen sheet (ice dam protection)
Correct Answer: B
Rationale:
Questions and Answers | 2026/2027 Edition |
Verified Questions & Correct Answers | State
Licensing Examination Preparation | Grade A
Guaranteed Study Guide
SECTION 1: ROOFING MATERIALS & FASTENERS
(Louisiana Gulf Coast Corrosion & Wind Resistance Emphasis)
Q1: When selecting fasteners for roofing installation in a home located within 3 miles of
the Louisiana Gulf Coast, what is the minimum corrosion resistance requirement per
IRC Section R905.1.1?
A. Galvanized with G-60 coating
B. Electro-galvanized finish
C. Hot-dipped galvanized with G-90 coating
D. Standard zinc-plated nails
Correct Answer: C
Rationale:
● ✅ C is correct: IRC Section R905.1.1 requires corrosion-resistant fasteners. For
coastal Louisiana within 3 miles of salt water, G-90 hot-dipped galvanized is the
minimum standard due to accelerated corrosion from salt air and high humidity.
This provides approximately 0.90 oz/ft² of zinc coating.
, ● ❌ A is wrong: G-60 coating (0.60 oz/ft²) provides insufficient protection for
❌ B is wrong: Electro-galvanized fasteners have thinner zinc coating (typically
coastal Louisiana's salt-laden environment and will corrode prematurely.
●
0.2-0.4 oz/ft²) applied electrolytically, creating less bond strength and failing
❌
within months in high-humidity coastal conditions.
● D is wrong: Standard zinc-plated nails lack sufficient corrosion resistance for
exterior roofing applications and will fail rapidly in Louisiana's humid subtropical
climate.
Q2: For asphalt shingles installed in Louisiana Wind Zone 2 (130+ mph design wind
speed), what is the minimum ASTM wind resistance rating required?
A. ASTM D3161, Class F (110 mph)
B. ASTM D3161, Class G (120 mph)
C. ASTM D7158, Class H (150 mph)
D. ASTM D3018, Type I only
Correct Answer: C
Rationale:
● ✅ C is correct: Louisiana Wind Zone 2 (southern parishes) requires ASTM
D7158 Class H (150 mph) or ASTM D3161 Class F (110 mph) with enhanced
fastening. However, most jurisdictions now require D7158 Class H for
❌
high-velocity hurricane zones to meet IRC R905.1.1 and LSUCC amendments.
● A is wrong: Class F (110 mph) is insufficient for Zone 2; adequate only for
❌
Wind Zone 1 (northern Louisiana, 90-110 mph).
● B is wrong: Class G (120 mph) does not exist in ASTM D3161; ratings are
❌
Class A (60 mph), D (90 mph), F (110 mph).
● D is wrong: ASTM D3018 is the standard specification for Class A, B, C fire
ratings, not wind resistance.
Q3: What is the minimum thickness requirement for roof sheathing (decking) in new
residential construction under the Louisiana State Uniform Construction Code?
, A. 3/8 inch plywood or OSB
B. 7/16 inch OSB with APA span rating 24/16
C. 15/32 inch (1/2 inch nominal) plywood or OSB
D. 5/8 inch plywood only
Correct Answer: C
Rationale:
● ✅ C is correct: IRC Table R503.1 requires minimum 15/32-inch (nominal 1/2
inch) plywood or OSB for roof sheathing when supports are spaced 16 inches on
❌
center. Louisiana amendments enforce this strictly due to wind uplift concerns.
● A is wrong: 3/8 inch is prohibited for roof sheathing under IRC; insufficient
❌
strength for wind loads.
● B is wrong: 7/16 inch OSB is permitted only for wall sheathing (24-inch o.c.
studs) or roof sheathing with 24-inch o.c. rafters in some jurisdictions, but 15/32
❌
inch is the safer, code-compliant minimum for standard roofing.
● D is wrong: 5/8 inch provides superior performance but is not the code
minimum; 15/32 inch is acceptable when properly installed.
Q4: In coastal Louisiana, what type of underlayment is required beneath asphalt
shingles on roof slopes between 2:12 and 4:12?
A. Single layer of 15-pound felt
B. Double layer of 15-pound felt with 19-inch headlap
C. Single layer of synthetic underlayment only
D. Self-adhering polymer-modified bitumen sheet (ice dam protection)
Correct Answer: B
Rationale:
