AL IN Insulation Contractor Exam
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. What is the primary purpose of insulation in buildings?
A. Increase indoor humidity
B. Absorb sound
C. Reduce heat flow
D. Increase structural stability
Answer: C
Rationale: Insulation’s core function is to slow heat transfer, improving
energy efficiency.
2. Which R-value represents thicker or more effective insulation?
A. R-5
B. R-11
C. R-19
D. R-2
Answer: C
Rationale: Higher R-values indicate improved thermal resistance.
3. Which insulation type is typically used in attics as loose-fill?
A. Rigid foam
B. Mineral wool batts
C. Spray polyurethane foam
D. Cellulose
Answer: D
Rationale: Loose-fill cellulose is common in attic retrofits.
,4. Fiberglass insulation is primarily made from:
A. Recycled rubber
B. Melted glass fibers
C. Compressed cellulose
D. Shredded plastic
Answer: B
Rationale: Fiberglass consists of spun or blown molten glass.
5. Which insulation material provides both air sealing and high R-value
per inch?
A. Fiberglass
B. Spray foam
C. Cellulose
D. Mineral wool
Answer: B
Rationale: Closed-cell spray foam has extremely high R-value and provides
air sealing.
6. The R-value of insulation is based on:
A. Thickness only
B. Woven density
C. Thermal resistance
D. Moisture permeability
Answer: C
Rationale: R-value measures resistance to heat flow.
7. A vapor barrier is typically placed on which side of a wall assembly in
cold climates?
A. Exterior side
B. Middle of wall cavity
C. Interior side
D. At the sheathing
Answer: C
Rationale: Vapor barriers go on the warm side to reduce condensation risk.
, 8. Which type of insulation can pose respiratory risks if inhaled during
installation?
A. Rigid foam
B. Fiberglass
C. Spray foam
D. Cellulose
Answer: B
Rationale: Fiberglass fibers irritate lungs, skin, and eyes.
9. Which insulation is best known for fire resistance?
A. Cellulose
B. Mineral wool
C. Polystyrene
D. Polyiso
Answer: B
Rationale: Mineral wool is naturally non-combustible.
10. Closed-cell spray foam typically has an R-value per inch of:
A. R-3
B. R-4.5
C. R-6 to R-7
D. R-2
Answer: C
Rationale: Closed-cell spray foam has the highest R-value among field-
installed insulation.
11. A thermal envelope refers to:
A. Only the exterior walls
B. Only the roof
C. All insulated building components
D. Mechanical equipment
Answer: C
Rationale: The thermal envelope includes conditioned-space boundaries.
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. What is the primary purpose of insulation in buildings?
A. Increase indoor humidity
B. Absorb sound
C. Reduce heat flow
D. Increase structural stability
Answer: C
Rationale: Insulation’s core function is to slow heat transfer, improving
energy efficiency.
2. Which R-value represents thicker or more effective insulation?
A. R-5
B. R-11
C. R-19
D. R-2
Answer: C
Rationale: Higher R-values indicate improved thermal resistance.
3. Which insulation type is typically used in attics as loose-fill?
A. Rigid foam
B. Mineral wool batts
C. Spray polyurethane foam
D. Cellulose
Answer: D
Rationale: Loose-fill cellulose is common in attic retrofits.
,4. Fiberglass insulation is primarily made from:
A. Recycled rubber
B. Melted glass fibers
C. Compressed cellulose
D. Shredded plastic
Answer: B
Rationale: Fiberglass consists of spun or blown molten glass.
5. Which insulation material provides both air sealing and high R-value
per inch?
A. Fiberglass
B. Spray foam
C. Cellulose
D. Mineral wool
Answer: B
Rationale: Closed-cell spray foam has extremely high R-value and provides
air sealing.
6. The R-value of insulation is based on:
A. Thickness only
B. Woven density
C. Thermal resistance
D. Moisture permeability
Answer: C
Rationale: R-value measures resistance to heat flow.
7. A vapor barrier is typically placed on which side of a wall assembly in
cold climates?
A. Exterior side
B. Middle of wall cavity
C. Interior side
D. At the sheathing
Answer: C
Rationale: Vapor barriers go on the warm side to reduce condensation risk.
, 8. Which type of insulation can pose respiratory risks if inhaled during
installation?
A. Rigid foam
B. Fiberglass
C. Spray foam
D. Cellulose
Answer: B
Rationale: Fiberglass fibers irritate lungs, skin, and eyes.
9. Which insulation is best known for fire resistance?
A. Cellulose
B. Mineral wool
C. Polystyrene
D. Polyiso
Answer: B
Rationale: Mineral wool is naturally non-combustible.
10. Closed-cell spray foam typically has an R-value per inch of:
A. R-3
B. R-4.5
C. R-6 to R-7
D. R-2
Answer: C
Rationale: Closed-cell spray foam has the highest R-value among field-
installed insulation.
11. A thermal envelope refers to:
A. Only the exterior walls
B. Only the roof
C. All insulated building components
D. Mechanical equipment
Answer: C
Rationale: The thermal envelope includes conditioned-space boundaries.
