Certified Energy Auditor Certification Building Envelope Assessment 2 — Questions and Answers
Question 1: Which metric best describes the overall thermal resistance of a wall assembly including framing members?
- Clear-field R-value
- Whole-wall R-value (Correct answer)
- Center-of-cavity R-value
- Effective U-factor
Correct answer: Whole-wall R-value
Whole-wall R-value accounts for all thermal bridges including framing, corners, and interface details, giving a more realistic measure than center-of-cavity R-value.
Question 2: A blower door test shows 8 ACH50 in a home. Which energy code category does this typically fall into?
- Extremely tight — exceeds Passive House standard
- Meets 2021 IECC requirement of ≤3 ACH50
- Leaky — exceeds the 2021 IECC limit (Correct answer)
- Within tolerance for commercial buildings
Correct answer: Leaky — exceeds the 2021 IECC limit
The 2021 IECC requires ≤3 ACH50 for most climate zones, so 8 ACH50 indicates a significantly leaky building.
Question 3: What is the primary concern with installing a vapor retarder on both sides of a wall cavity?
- It doubles installation cost unnecessarily
- Moisture trapped inside cannot dry to either side (Correct answer)
- It violates fire code requirements
- It reduces the effective R-value of insulation
Correct answer: Moisture trapped inside cannot dry to either side
A double vapor retarder traps moisture within the cavity, preventing drying and promoting mold growth and structural decay.
Question 4: In a thermographic survey, which color in a standard palette typically indicates the coolest surface temperature on an exterior wall scan in heating season?
- Red or white
- Yellow or orange
- Blue or purple (Correct answer)
- Green
Correct answer: Blue or purple
In a standard thermal palette, blue and purple represent the lowest temperatures, which on an exterior wall in heating season indicate areas of heat loss or insulation deficiency.
Question 5: What does 'thermal mass' primarily contribute to in a building envelope?
- Reduced air infiltration
- Time-shifted peak heat gain or loss (Correct answer)
- Increased R-value of walls
- Improved vapor diffusion resistance
Correct answer: Time-shifted peak heat gain or loss
Thermal mass stores heat energy and releases it slowly, shifting the timing of peak loads rather than directly increasing insulation resistance.
Question 6: Which window specification parameter directly indicates how much solar heat enters through the glazing?
- Visible transmittance (VT)
- U-factor
- Solar heat gain coefficient (SHGC) (Correct answer)
- Air leakage rating
Correct answer: Solar heat gain coefficient (SHGC)
SHGC measures the fraction of incident solar radiation admitted through a window, directly quantifying solar heat gain.
Question 7: An auditor identifies significant frost forming on interior window surfaces in winter. What is the most likely cause?
- High SHGC glazing allowing too much solar gain
- Inadequate frame U-factor combined with high indoor humidity (Correct answer)
- Improperly installed window flashing
- Missing interior window stop
Correct answer: Inadequate frame U-factor combined with high indoor humidity
Interior frost occurs when the window surface temperature drops below the dew point of the indoor air, typically due to a high (poor) frame U-factor and excessive indoor humidity.
Certified Energy Auditor Certification Building Envelope Assessment 2
Which metric best describes the overall thermal resistance of a wall assembly including framing members?