Home Inspector Test Home Inspector Insulation and Ventilation 1 — Questions and Answers
Question 1: What is the minimum recommended R-value for attic insulation in a cold US climate zone (Zone 5–8)?
- R-19
- R-30
- R-49 (Correct answer)
- R-60
Correct answer: R-49
The US Department of Energy recommends R-49 to R-60 for attic insulation in cold climate zones 5–8.
Question 2: Which type of insulation is most commonly found loose-filled in older attics and may contain asbestos?
- Fiberglass batts
- Vermiculite (Correct answer)
- Spray foam
- Cellulose
Correct answer: Vermiculite
Vermiculite insulation, often mined from Libby, Montana, is commonly contaminated with asbestos and was widely used as loose-fill attic insulation.
Question 3: What is the purpose of a vapor retarder installed on the warm side of insulation?
- Improve R-value
- Prevent moisture migration into wall or ceiling cavities (Correct answer)
- Act as a fire barrier
- Reduce air infiltration only
Correct answer: Prevent moisture migration into wall or ceiling cavities
A vapor retarder limits the movement of moisture-laden air from the conditioned space into insulated cavities where it could condense and cause damage.
Question 4: A home inspector finds that attic insulation is blocking soffit vents. What is the primary concern?
- Reduced R-value of the insulation
- Restricted attic ventilation leading to moisture and heat buildup (Correct answer)
- Fire hazard from insulation contact with wood
- Pest entry through vents
Correct answer: Restricted attic ventilation leading to moisture and heat buildup
Blocked soffit vents prevent proper intake airflow, causing heat and moisture to accumulate in the attic, which can damage sheathing and shorten shingle life.
Question 5: What is the standard net free area ventilation ratio required by most US building codes for attic ventilation?
- 1:100
- 1:150 (Correct answer)
- 1:200
- 1:300
Correct answer: 1:150
Building codes generally require a minimum of 1 square foot of net free ventilation area for every 150 square feet of attic floor space.
Question 6: Which insulation material has the highest R-value per inch?
- Fiberglass batt
- Open-cell spray foam
- Closed-cell spray foam (Correct answer)
- Cellulose
Correct answer: Closed-cell spray foam
Closed-cell spray polyurethane foam achieves approximately R-6 to R-7 per inch, the highest of common insulation types.
Home Inspector Test Home Inspector Insulation and Ventilation 1
What is the minimum recommended R-value for attic insulation in a cold US climate zone (Zone 5–8)?