HERS Study Guide 2026
Everything you need to pass the HERS exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 HERS Exam Format at a Glance
📚 HERS Topics to Study (63)
✍️ Sample HERS Questions & Answers
1. In hot-humid climates, which vapor control strategy is generally recommended for wall assemblies?
In hot-humid climates, walls should be able to dry to either the interior or exterior; trapping moisture with vapor retarders on either side causes problems.
2. Which water heater type typically has the highest UEF rating?
Heat pump water heaters achieve UEF ratings of 3.0 or higher because they move heat from surrounding air rather than generating it directly, making them 2-3 times more efficient than electric resistance units.
3. A rater discovers that the installed attic insulation is R-30 instead of the specified R-49. How does this affect the HERS score?
Less insulation than specified increases heat transfer through the attic, raising heating and cooling energy loads and resulting in a higher (worse) HERS Index score.
4. Which software setting must be configured correctly to distinguish between a conditioned basement and an unconditioned crawl space?
Foundation type and its conditioning status determine how the software calculates heat loss/gain through below-grade assemblies.
5. What is a 'guarded blower door test' (also called a two-fan test) used to measure?
A guarded (two-fan) blower door test uses one fan in each of two adjacent units to equalize pressure between them, allowing measurement of only the leakage to the outside from each unit in multifamily buildings.
6. What HERS Index score must a home achieve to qualify for the ENERGY STAR Certified Homes Version 3.2 program (new construction)?
ENERGY STAR Certified Homes Version 3.2 requires a HERS Index of 57 or below, with the exact threshold varying by climate zone.