Download Alabama Insulation Exam: Practice Questions and Answers and more Exams Technology in PDF only on Docsity!
Question 1. Which heat‑transfer method moves energy through a solid material without bulk movement of the material? A) Convection B) Radiation C) Conduction D) Diffusion Answer: C Explanation: Conduction transfers heat through molecular vibration in solids; there is no fluid motion. Question 2. In a building envelope, which control method is most effective for reducing radiant heat gain from the sun? A) Adding dense‑packed cellulose B) Installing a reflective radiant barrier on the attic floor C) Sealing air leaks around windows D) Using mineral‑wool batts in walls Answer: B Explanation: Reflective radiant barriers reflect infrared radiation, lowering solar heat gain. Question 3. The R‑value of a material is defined as: A) The rate of heat flow per unit area per degree temperature difference B) The resistance to heat flow per unit thickness C) The inverse of thermal conductivity multiplied by thickness D) The amount of heat stored per unit volume Answer: C Explanation: R‑value = thickness ÷ thermal conductivity; it is the inverse of U‑factor. Question 4. If a wall assembly has an R‑value of 20 ft²·°F·h/BTU, what is its U‑factor? A) 0.05 BTU/(h·ft²·°F) B) 20 BTU/(h·ft²·°F)
C) 0.2 BTU/(h·ft²·°F) D) 5 BTU/(h·ft²·°F) Answer: A Explanation: U = 1 ÷ R, so 1 ÷ 20 = 0.05. Question 5. Thermal bridging is best minimized by: A) Using thicker batt insulation only B) Installing continuous exterior insulation C) Adding interior vapor barriers D) Increasing interior air temperature Answer: B Explanation: Continuous exterior insulation breaks the path of conductive studs, reducing bridging. Question 6. The dew point is the temperature at which: A) Air reaches 100 % relative humidity and moisture begins to condense B) Heat flow through a wall stops C) Air pressure equals vapor pressure D) Moisture migrates outward from a wall cavity Answer: A Explanation: Dew point is the temperature where air becomes saturated and condensation occurs. Question 7. Which of the following insulation types has the highest typical R‑value per inch? A) Fiberglass batt B) Cellulose loose‑fill C) Closed‑cell spray foam D) Mineral‑wool board Answer: C Explanation: Closed‑cell spray foam provides about R‑6 to R‑7 per inch, higher than the others.
B) Seamless and airtight across the entire thermal envelope C) Perforated to allow drying to the exterior D) Located behind the interior drywall only Answer: B Explanation: The code mandates a continuous, unbroken air barrier to control infiltration. Question 12. Which sealing technique is recommended for electrical boxes on exterior walls? A) Caulking with silicone only around the box exterior B) Using foam gasket kits that seal both the interior and exterior gaps C) Leaving the box unsealed if the wall cavity is insulated D) Applying duct tape over the box cover Answer: B Explanation: Foam gasket kits provide a complete air‑tight seal around the box, meeting code. Question 13. When insulating a rim joist, the most effective method is: A) Installing unfaced fiberglass batts only on the interior side B) Applying spray‑foam insulation to fill all gaps, then covering with rigid board C) Using loose‑fill cellulose only on the exterior side D) Leaving the rim joist uninsulated and focusing on the floor above Answer: B Explanation: Closed‑cell spray foam fills gaps and provides an air barrier; rigid board adds continuous insulation. Question 14. The Building Envelope Tightness (BET) test measures: A) The total heat loss through walls B) The number of air changes per hour at 50 Pa (ACH50) C) The moisture vapor diffusion rate D) The R‑value of the roof assembly Answer: B
Explanation: BET (blower door) test quantifies air leakage as ACH50. Question 15. The maximum allowable duct leakage for a newly constructed home in Alabama is: A) 5 % of the total conditioned floor area B) 10 % of the total design airflow (CFM) C) 2 % of the total building volume per hour D) 3 % of the total design airflow (CFM) Answer: B Explanation: The IRC limits duct leakage to 10 % of the design airflow for new homes. Question 16. When installing fiberglass batt insulation, the kraft paper facing should be placed: A) Toward the conditioned interior space in warm‑climate zones B) Toward the exterior sheathing in all climates C) Only when a vapor barrier is required on the interior side D) Never; kraft paper is not a vapor barrier Answer: C Explanation: Kraft paper acts as a Class III vapor retarder and is used on the interior side when a vapor barrier is needed. Question 17. The proper method for cutting fiberglass batts around a pipe is: A) Scoring with a utility knife and pulling the batt apart B) Using a hot wire cutter for a clean edge C) Cutting the pipe out of the batt after installation D) Leaving a gap of at least 1 in. around the pipe Answer: A Explanation: Scoring and pulling creates a precise opening that maintains continuous contact. Question 18. For loose‑fill cellulose, the recommended minimum density to achieve target R‑value without excessive settling is:
D) It cannot support structural loads without a barrier Answer: B Explanation: Closed‑cell foam is a plastic that must be covered with a 15‑minute thermal barrier (e.g., drywall) per code. Question 22. When installing rigid‑board insulation on an exterior wall, seams should be sealed with: A) Construction adhesive only B) Foil‑taped joint sealant rated for the board material C) Duct tape D) No sealing is required if boards are tightly butted Answer: B Explanation: Proper tape and sealant prevent air infiltration and moisture penetration at joints. Question 23. The primary function of a radiant barrier installed under attic rafters is to: A) Increase R‑value of the roof assembly B) Reflect solar radiation, reducing heat gain in the attic C) Act as a vapor barrier for the roof deck D) Provide structural support for insulation Answer: B Explanation: Radiant barriers reflect infrared energy, keeping attic temperatures lower. Question 24. Class III vapor retarders have a permeance of: A) 0 perm B) 0.1 perm or less C) 1 perm to 10 perm D) Greater than 10 perm Answer: C Explanation: Class III retarders allow limited vapor diffusion (1–10 perm).
Question 25. In Alabama’s mixed‑climate zones, the recommended location for a vapor retarder in a wall assembly is: A) Directly against the exterior sheathing B) On the interior side of the framing, adjacent to drywall C) In the middle of the cavity between studs D) No vapor retarder is required in any zone Answer: B Explanation: In mixed climates, interior placement helps control interior moisture migration. Question 26. The net free ventilation area (NFVA) required for a 1,200 ft² attic with a minimum of 1 ft³/min per ft² of attic floor area is: A) 12 in² B) 120 in² C) 1,200 in² D) 12,000 in² Answer: C Explanation: Required ventilation = 1 ft³/min per ft² = 1 ft³/min; NFVA = 1 ft³/min × 144 in²/ft³ = 144 in² per 1 ft², but the code uses 1 ft² of NFVA per 150 ft² of attic floor. Using 1,200 ft² → 8 ft² = 1152 in² (≈1,200 in²). Question 27. Baffles (chutes) installed in an attic serve to: A) Increase R‑value of the insulation B) Keep insulation from blocking airflow from soffit vents to the ridge C) Provide a fire‑stop between insulation and roof deck D) Act as a vapor barrier for the attic space Answer: B Explanation: Baffles create a channel for ventilation air to flow freely above the insulation. Question 28. For an unvented crawl space, the recommended ground cover material is:
D) No specific sequence; both can be done simultaneously Answer: B Explanation: Insulation must be placed before the interior finish to avoid damaging the finish and to maintain continuous coverage. Question 32. Which PPE is mandatory when applying closed‑cell spray foam? A) Disposable nitrile gloves only B) Full‑face respirator with organic vapor cartridges, goggles, and coveralls C) Ear plugs and hard hat D) Safety glasses and dust mask (N95) Answer: B Explanation: Closed‑cell foam releases isocyanates; a full‑face respirator, goggles, and protective clothing are required. Question 33. OSHA 1926.651(b)(1) requires fall protection when working at heights greater than: A. 4 ft B. 6 ft C. 8 ft D. 10 ft Answer: B Explanation: The standard mandates fall protection for work over 6 ft high. Question 34. The Hazard Communication Standard (HAZCOM) requires that every container of insulation chemicals have: A) A barcode for inventory tracking B) A Safety Data Sheet (SDS) readily accessible to workers C) A color‑coded label only D) A CE marking for European compliance Answer: B Explanation: HAZCOM mandates an SDS for each hazardous product.
Question 35. In a fire‑stop assembly for a wall penetration, the minimum required fire‑resistive rating is: A) 30 minutes B) 60 minutes C) 90 minutes D) 120 minutes Answer: B Explanation: The IRC generally requires a 60‑minute fire stop for wall penetrations. Question 36. Which insulation material is naturally resistant to mold and does not require a separate moisture barrier? A) Fiberglass batts B) Cellulose loose‑fill C) Closed‑cell spray foam D) Rock‑wool (mineral wool) batts Answer: D Explanation: Mineral wool is water‑repellent and mold‑resistant, eliminating the need for a separate barrier. Question 37. The most common cause of insulation settling in attics is: A) Excessive moisture exposure B) Improperly installed rigid board C) Using low‑density loose‑fill cellulose without dense‑pack D) Over‑compressing fiberglass batts Answer: C Explanation: Low‑density loose‑fill can settle over time, reducing R‑value. Question 38. When installing rigid‑board insulation on a concrete foundation wall, the board should be:
Answer: B Explanation: Fire‑blocking stops fire from traveling up wall cavities. Question 42. Which of the following statements about spray‑foam expansion ratios is correct? A) Open‑cell foam expands about 20‑ 30 times its liquid volume B) Closed‑cell foam expands about 3‑ 4 times its liquid volume C) Both open‑ and closed‑cell foams have the same expansion ratio D) Expansion ratio is irrelevant for calculating material quantity Answer: B Explanation: Closed‑cell foam typically expands 3– 4 times; open‑cell expands 20– 30 times. Question 43. When installing batt insulation in a wall with 2 × 6 studs, the recommended thickness of the batt to achieve full cavity fill is: A) 3 in. B) 5 in. C) 5.5 in. D) 6 in. Answer: C Explanation: A 2 × 6 cavity is 5.5 in. deep; a 5.5‑in. batt fills it without compression. Question 44. The most effective way to prevent thermal bridging at a wall corner is to: A) Use a thicker batt in the corner cavity only B) Install a continuous exterior rigid‑board that wraps around the corner C) Fill the corner with loose‑fill cellulose only D) Leave the corner uninsulated to allow heat flow Answer: B Explanation: Continuous exterior insulation that wraps the corner eliminates the stud bridge.
Question 45. In a building with an unconditioned garage above a finished floor, the floor assembly must include: A) R‑10 insulation under the floor joists only B) R‑19 insulation between the joists and a sealed rim joist C) No insulation, as the garage is unconditioned D) Only a vapor barrier on the garage ceiling Answer: B Explanation: The IRC requires insulation between joists and a sealed rim joist for floors over unconditioned spaces. Question 46. Which of the following is a primary advantage of mineral‑wool over fiberglass for attic insulation? A) Higher R‑value per inch B) Better fire resistance and sound absorption C) Lower cost per square foot D) Easier to compress into tight spaces Answer: B Explanation: Mineral wool is non‑combustible and offers superior acoustic performance. Question 47. The required air‑tightness for a new home in Alabama, expressed as ACH50, is: A) ≤ 3 ACH B) ≤ 5 ACH C) ≤ 7 ACH D) ≤ 10 ACH Answer: B Explanation: Many jurisdictions adopt a target of ≤ 5 ACH50 for new residential construction. Question 48. When installing a vapor barrier over a concrete slab, the barrier should be: A) Placed directly on the concrete without a sealant B) Overlapped at least 6 in. and taped with a compatible vapor‑retarder tape
Explanation: Continuous insulation breaks the conductive path of studs, raising the wall’s thermal performance. Question 52. When using spray‑foam on a roof deck, the installer must protect the deck from: A) UV radiation during cure B) Excessive moisture infiltration after cure C) Both A and B D) Neither; foam protects the deck automatically Answer: C Explanation: UV can degrade uncured foam, and moisture can compromise adhesion; both must be managed. Question 53. The correct method for installing a vapor‑retarder on the interior side of a wall with existing drywall is to: A) Staple the vapor‑retarder directly to the studs before drywall installation B) Apply the vapor‑retarder over the finished drywall using a spray‑on coating C) Install a separate interior vapor‑retarder panel before drywall and tape seams D) No vapor‑retarder is needed if the wall already has fiberglass batts Answer: C Explanation: The vapor‑retarder must be placed on the warm side of the assembly, typically behind drywall. Question 54. In a mixed‑climate zone, the recommended NFVA for attic ventilation is: A) 1 ft² of vent area per 150 ft² of attic floor area B) 1 ft² of vent area per 300 ft² of attic floor area C) 2 ft² of vent area per 150 ft² of attic floor area D) No ventilation required if insulation is > R‑ 38 Answer: A Explanation: The standard 1 ft² per 150 ft² ratio applies.
Question 55. The term “air infiltration” refers to: A) Moisture moving through a wall assembly B) Uncontrolled air movement into or out of a building envelope through cracks and openings C) Heat flow due to temperature differences D) The diffusion of vapor through a vapor barrier Answer: B Explanation: Infiltration is the uncontrolled passage of air through the building envelope. Question 56. Which of the following insulation installation practices helps prevent “thermal short‑circuiting” in a wall? A) Compressing batts tightly against studs B) Leaving gaps between insulation and sheathing C) Installing continuous exterior insulation over studs and sheathing D) Using only interior insulation with no exterior layer Answer: C Explanation: Continuous exterior insulation eliminates conductive paths that cause short‑circuiting. Question 57. The required R‑value for foundation walls in Alabama Climate Zone 3 is: A) R‑ 5 B) R‑ 10 C) R‑ 13 D) R‑ 20 Answer: C Explanation: Zone 3 mandates a minimum of R‑13 for foundation walls. Question 58. When using a blower‑door test, a reading of 0.5 ACH50 indicates: A) Excellent airtightness, well below the typical target B) Poor airtightness, exceeding most code limits C) A moderate level of leakage, acceptable for most homes
Question 62. In an insulated concrete form (ICF) wall, the interior insulation is typically: A) Fiberglass batts placed after the concrete cures B) The expanded polystyrene (EPS) that forms the form itself C) Rigid‑board installed on the interior side only D) No insulation needed because concrete has high R‑value Answer: B Explanation: ICF walls use the EPS form as continuous insulation on both sides of the concrete. Question 63. When installing spray foam in a wall cavity, the recommended maximum spray depth per pass is: A) 1 in. B) 2 in. C) 3 in. D) 4 in. Answer: B Explanation: Limiting depth to about 2 in. per pass ensures proper curing and reduces sagging. Question 64. Which of the following is a correct statement about “Class II” vapor retarders? A) They have a permeance of 0 perm B) They allow limited vapor diffusion (0.1–1 perm) C) They are completely impermeable to vapor D) They are only used in exterior wall assemblies Answer: B Explanation: Class II retarders have a permeance between 0.1 and 1 perm. Question 65. The correct way to seal a gap around a recessed lighting fixture that is not IC‑rated is to: A) Install a fire‑rated box and seal with foil tape B) Fill the gap with expanding spray foam only
C) Leave the gap open for future access D) Use a metal plate over the fixture without sealing Answer: A Explanation: A fire‑rated box provides the required fire protection, and sealing ensures air‑tightness. Question 66. For a wall assembly that includes 2 × 4 studs, 3.5 in. cavity insulation, and 1 in. exterior rigid board, the overall R‑value (ignoring thermal bridging) is approximately: A) R‑ 13 B) R‑ 19 C) R‑ 25 D) R‑ 30 Answer: C Explanation: Approximate values: 2 × 4 cavity R‑13 + 1‑in. rigid board R‑5 = R‑18; adding stud thermal bridge reduction (~10 %) yields about R‑ 20 – R‑22; the closest answer is R‑25, reflecting a typical design value. Question 67. The most common cause of moisture damage in attic insulation is: A) Over‑compression of batts B) Inadequate ventilation leading to condensation on the underside of the roof deck C) Using reflective foil on the warm side of the attic D) Installing too much insulation (R‑> 60) Answer: B Explanation: Poor ventilation traps moisture, causing condensation and insulation degradation. Question 68. When performing a duct leakage test, “Total Leakage” is measured in: A) CFM at 0 Pa B) CFM at 75 Pa C) L/s at 50 Pa D) ACH Answer: B
