HERS Building Science Principles Questions and Answers

Question 1

Which of the following best describes the 'house-as-a-system' concept in building science?

Accepted Answer

The idea that the building envelope, mechanical systems, occupants, and environment are interconnected, and a change in one can affect the performance of the others.

Answer

Viewing a house as a collection of independent components, where changes to one part have minimal effect on the others.

Answer

A construction method that prioritizes the use of sustainable and recycled building materials exclusively.

Answer

A design philosophy that focuses solely on the aesthetic and architectural style of a home, independent of its energy performance.

Question 2

During a winter energy audit, a HERS Rater observes significant frost on the nails in the attic sheathing. This is most likely an indicator of what building science phenomenon?

Accepted Answer

Air leakage from the conditioned space carrying warm, moist air into the cold attic, where it condenses and freezes on cold surfaces.

Answer

Heat transfer primarily through radiation from the roofing material.

Answer

A properly functioning radiant barrier reflecting heat back into the conditioned space.

Answer

Excessive solar heat gain through the roof assembly.

Question 3

A two-story home in a cold climate experiences drafts near the floor on the first level and feels stuffy on the second level during the winter. This condition is most likely caused by:

Accepted Answer

Stack effect

Answer

Reverse stack effect

Answer

The Venturi effect

Answer

Capillary action

Question 4

What are the three primary mechanisms of heat transfer that a HERS Rater must consider when evaluating a building's thermal envelope?

Accepted Answer

Conduction, Convection, and Radiation

Answer

Infiltration, Exfiltration, and Ventilation

Answer

Air Pressure, Moisture Content, and Temperature

Answer

Evaporation, Condensation, and Sublimation

Question 5

A homeowner in a hot, humid climate decides to add a polyethylene vapor barrier to the interior side of their insulated walls during a remodel. What is the most likely outcome of this decision?

Accepted Answer

Trapping moisture within the wall cavity, leading to potential mold and rot.

Answer

Improved energy efficiency by stopping all heat transfer.

Answer

No significant impact on the wall assembly's performance.

Answer

A significant reduction in exterior noise transmission.

Question 6

The building science mantra "Build Tight, Ventilate Right" refers to which of the following concepts?

Accepted Answer

Sealing the building envelope to control random air leakage and then providing fresh air through a controlled, mechanical ventilation system.

Answer

Constructing a building with many intentional openings to promote natural air flow.

Answer

Using mechanical ventilation as the primary means of air sealing a building envelope.

Answer

Ensuring all ventilation ductwork is sealed with mastic, regardless of the building's air tightness.