HERS Index and Ratings

Question 1

A home receives a HERS Index of 0. What does this indicate?

Accepted Answer

The home uses no net energy on an annual basis

Answer

A HERS Index of 0 represents a net zero energy home that produces as much energy as it consumes annually.

Question 2

Which of the following scenarios would most likely INCREASE a home's HERS Index score?

Accepted Answer

Increasing duct leakage from 4% to 10%

Answer

Increasing duct leakage wastes conditioned air and raises energy consumption, which increases the HERS Index score.

Question 3

When a HERS rater upgrades a home's insulation from R-11 to R-19 in the walls, what is the expected effect on the HERS Index?

Accepted Answer

The HERS Index decreases

Answer

Better insulation reduces heat transfer and energy demand, which lowers the HERS Index score.

Question 4

The HERS reference home is set to an index of 100 and is modeled based on which standard?

Accepted Answer

RESNET/ICC 301 standard

Answer

The HERS reference home is defined by the RESNET/ICC 301 standard, establishing the baseline for index calculations.

Question 5

A new home scores a HERS 55 and its neighbor scores a HERS 85. Approximately how much more energy efficient is the first home?

Accepted Answer

About 30% more efficient

Answer

Each point on the HERS scale represents approximately 1% more or less energy use, so a 30-point difference equals roughly 30% greater efficiency.

(HERS) Certified Home Energy Rating System Rater Practice Test