C 39 ROOFING TRADE TEST 1 AND TEST 2 (COMPLETE TESTS) | QUESTIONS AND
CORRECT ANSWERS | ALREADY GRADED A+ | VERIFIED ANSWERS | LATEST VERSIONS
Question 1
Composition flashing (base flashing) should be fastened using which of the following methods?
A) Staples driven at 2-inch intervals
B) One-inch solid cap-head nails or nails driven through tin disks
C) Standard roofing nails without washers
D) Hot asphalt mopping only
E) Double-sided butyl tape
Correct Answer: B) One-inch solid cap-head nails or nails driven through tin disks
Rationale: According to standard roofing practices for composition or base flashing,
fasteners must have a wide head or use a tin disk to provide enough surface area to prevent
the flashing material from tearing away or pulling over the nail head due to wind uplift or
thermal expansion.
Question 2
Why are pitch pockets or pitch boxes generally not recommended in modern roofing
installations?
A) They are too expensive to install initially
B) They increase the weight of the roof beyond structural limits
C) They require extensive and frequent maintenance to remain watertight
D) They interfere with the chemical composition of TPO membranes
E) They are prohibited by the California Building Code in all zones
Correct Answer: C) They require extensive and frequent maintenance to remain watertight
Rationale: Pitch pockets rely on a pourable sealer that tends to shrink, crack, or pull away
from the penetration over time. Because of this, they are prone to leaks unless they are
constantly inspected and "topped off" with new sealer, making them a high-maintenance
detail.
Question 3
When using reinforced concrete as a structural deck, what is a critical factor regarding its
moisture content?
A) Concrete is completely dry 24 hours after pouring
B) Some moisture will remain in concrete decks even after the surface appears dry
C) Concrete decks never require a vapor retarder
D) Moisture in concrete actually improves the adhesion of hot asphalt
E) Concrete decks should be primed with water-based paint to trap moisture
Correct Answer: B) Some moisture will remain in concrete decks even after the surface
appears dry
Rationale: Concrete is a porous material that retains "latent moisture" deep within its
structure long after the surface feels dry to the touch. If a roofing system is installed over a
, 2
deck with high latent moisture without proper venting, it can lead to blistering or adhesion
failure.
Question 4
In northern or colder climates, how is roofing insulation and membranes typically protected from
latent moisture in concrete decks?
A) By applying a thick layer of gravel
B) By using a vapor retarder or a venting sheet
C) By increasing the number of fasteners per square
D) By installing the roof only during the summer months
E) By using only dark-colored membranes to increase heat
Correct Answer: B) By using a vapor retarder or a venting sheet
Rationale: Vapor retarders prevent moisture from moving into the insulation from the deck,
while venting sheets allow trapped moisture to migrate to the roof perimeters or vents. This
prevents the buildup of vapor pressure that can destroy the roof assembly.
Question 5
What is the minimum recommended thickness/gauge for steel decks used in roofing?
A) 28g
B) 26g
C) 24g
D) 22g or heavier
E) 18g only
Correct Answer: D) 22g or heavier
Rationale: Steel roof decks must be at least 22 gauge to provide the necessary structural
rigidity and to ensure that mechanical fasteners (screws) have enough material thickness to
"bite" into and achieve the required pull-out resistance.
Question 6
When applying insulation to steel roof decks before the roof membrane is installed, how should
it be applied if the thickness permits?
A) In one single, thick layer to save labor
B) In two separate layers with staggered joints
C) Vertically rather than horizontally
D) Glued with wood glue
E) Without any mechanical fasteners
Correct Answer: B) In two separate layers where insulation thickness permits
Rationale: Installing insulation in two layers with staggered joints (offsetting the seams)
significantly reduces thermal bridging and prevents a direct path for air or vapor to
migrate through the seams, improving the overall R-value and stability of the system.
CORRECT ANSWERS | ALREADY GRADED A+ | VERIFIED ANSWERS | LATEST VERSIONS
Question 1
Composition flashing (base flashing) should be fastened using which of the following methods?
A) Staples driven at 2-inch intervals
B) One-inch solid cap-head nails or nails driven through tin disks
C) Standard roofing nails without washers
D) Hot asphalt mopping only
E) Double-sided butyl tape
Correct Answer: B) One-inch solid cap-head nails or nails driven through tin disks
Rationale: According to standard roofing practices for composition or base flashing,
fasteners must have a wide head or use a tin disk to provide enough surface area to prevent
the flashing material from tearing away or pulling over the nail head due to wind uplift or
thermal expansion.
Question 2
Why are pitch pockets or pitch boxes generally not recommended in modern roofing
installations?
A) They are too expensive to install initially
B) They increase the weight of the roof beyond structural limits
C) They require extensive and frequent maintenance to remain watertight
D) They interfere with the chemical composition of TPO membranes
E) They are prohibited by the California Building Code in all zones
Correct Answer: C) They require extensive and frequent maintenance to remain watertight
Rationale: Pitch pockets rely on a pourable sealer that tends to shrink, crack, or pull away
from the penetration over time. Because of this, they are prone to leaks unless they are
constantly inspected and "topped off" with new sealer, making them a high-maintenance
detail.
Question 3
When using reinforced concrete as a structural deck, what is a critical factor regarding its
moisture content?
A) Concrete is completely dry 24 hours after pouring
B) Some moisture will remain in concrete decks even after the surface appears dry
C) Concrete decks never require a vapor retarder
D) Moisture in concrete actually improves the adhesion of hot asphalt
E) Concrete decks should be primed with water-based paint to trap moisture
Correct Answer: B) Some moisture will remain in concrete decks even after the surface
appears dry
Rationale: Concrete is a porous material that retains "latent moisture" deep within its
structure long after the surface feels dry to the touch. If a roofing system is installed over a
, 2
deck with high latent moisture without proper venting, it can lead to blistering or adhesion
failure.
Question 4
In northern or colder climates, how is roofing insulation and membranes typically protected from
latent moisture in concrete decks?
A) By applying a thick layer of gravel
B) By using a vapor retarder or a venting sheet
C) By increasing the number of fasteners per square
D) By installing the roof only during the summer months
E) By using only dark-colored membranes to increase heat
Correct Answer: B) By using a vapor retarder or a venting sheet
Rationale: Vapor retarders prevent moisture from moving into the insulation from the deck,
while venting sheets allow trapped moisture to migrate to the roof perimeters or vents. This
prevents the buildup of vapor pressure that can destroy the roof assembly.
Question 5
What is the minimum recommended thickness/gauge for steel decks used in roofing?
A) 28g
B) 26g
C) 24g
D) 22g or heavier
E) 18g only
Correct Answer: D) 22g or heavier
Rationale: Steel roof decks must be at least 22 gauge to provide the necessary structural
rigidity and to ensure that mechanical fasteners (screws) have enough material thickness to
"bite" into and achieve the required pull-out resistance.
Question 6
When applying insulation to steel roof decks before the roof membrane is installed, how should
it be applied if the thickness permits?
A) In one single, thick layer to save labor
B) In two separate layers with staggered joints
C) Vertically rather than horizontally
D) Glued with wood glue
E) Without any mechanical fasteners
Correct Answer: B) In two separate layers where insulation thickness permits
Rationale: Installing insulation in two layers with staggered joints (offsetting the seams)
significantly reduces thermal bridging and prevents a direct path for air or vapor to
migrate through the seams, improving the overall R-value and stability of the system.
