CCP Building Envelope & Energy Audit 3

Question 1

During an energy audit, a commissioning professional evaluates a building's Energy Use Intensity (EUI). For a typical US office building, which EUI range (kBtu/ft²/year) is generally considered good performance?

Accepted Answer

50–75

Answer

A good-performing US office building typically achieves an EUI of 50–75 kBtu/ft²/year, significantly below the national median of approximately 90 kBtu/ft²/year.

Question 2

What is the key distinction between a vapor retarder and an air barrier in building envelope design?

Accepted Answer

Air barriers resist bulk airflow while vapor retarders resist water vapor diffusion by concentration gradient

Answer

Air barriers resist bulk airflow driven by pressure differences, while vapor retarders resist moisture diffusion driven by vapor pressure concentration gradients — they address different moisture transport mechanisms.

Question 3

A commissioning professional performing a pre-functional checklist for a curtain wall system should verify which critical installation detail to prevent condensation on interior surfaces?

Accepted Answer

Thermal breaks are properly installed at all metal framing members

Answer

Thermal breaks in curtain wall framing prevent cold metal from conducting to the interior surface, where condensation would form when interior dew point exceeds the surface temperature.

Question 4

An ASHRAE Level II energy audit of a grocery store reveals that refrigerated display cases account for 45% of total electricity use. What energy conservation measure (ECM) would most effectively reduce this consumption?

Accepted Answer

Adding night curtains/covers to open refrigerated display cases

Answer

Night curtains on open refrigerated display cases can reduce case energy consumption by 25–40%, representing substantial savings given that cases are typically the dominant energy load in grocery stores.

Question 5

In the context of building envelope commissioning, what does 'hygrothermal analysis' evaluate?

Accepted Answer

The combined heat and moisture transfer through building assemblies to predict condensation risk

Answer

Hygrothermal analysis (using tools like WUFI) models both heat and moisture transport through building assemblies to predict where and when condensation might occur, guiding insulation placement and vapor control strategies.

(CCP) Certified Commissioning Professional Practice Test

(CCP) Certified Commissioning Professional Practice Test

CCP Building Envelope & Energy Audit 3