Energy Modeling & Rating Systems Flashcards
7 cards from real HERS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Energy Modeling & Rating Systems flashcards as text
A rater finds that duct leakage to the outside is 8% of system airflow. How does this compare to the ENERGY STAR v3.1 threshold?
Answer: It fails; ENERGY STAR requires 4% or less
ENERGY STAR v3.1 requires total duct leakage to outside of 4% or less of system airflow capacity for compliance.
Which software feature allows a HERS rater to model a home with both a gas furnace and a heat pump operating together?
Answer: Hybrid heating system input
A hybrid heating system input in energy rating software allows modeling of dual-fuel configurations where a heat pump and backup furnace operate together.
What happens to a home's HERS score if window area is significantly increased without changing window U-factor or SHGC?
Answer: Score typically worsens due to increased conductive losses and solar gains
Increasing window area with the same U-factor and SHGC increases both conductive heat loss and unwanted solar gain, generally raising the HERS score.
Under RESNET standards, what is the maximum allowed difference between the rated and confirmed home for a sampled HERS rating to be valid?
Answer: 5 HERS points
RESNET sampling protocols allow a maximum 5 HERS point difference between the sampled reference home and the confirmed homes in the same community.
When entering window data into energy modeling software, which property most affects summer cooling loads in a South-facing application?
Answer: Solar heat gain coefficient (SHGC)
SHGC controls how much solar radiation passes through the window as heat, making it the dominant factor for cooling loads from solar-exposed windows.
A HERS rater is modeling a home with an attached garage. How should the garage typically be classified in the energy model?
Answer: As unconditioned space outside the thermal boundary
Attached garages are typically unconditioned spaces; the thermal boundary runs along the walls, floor, and ceiling separating the garage from the living area.
Which HERS rating pathway allows a rater to use prescriptive compliance for some components while modeling others?
Answer: Simulated Performance Pathway
The Simulated Performance Pathway allows raters to model actual home performance, combining prescriptive and performance approaches within a single energy simulation.