HERS Building Science Principles 2

Question 1

Which phenomenon causes warm, moist air to condense on a cold surface inside a wall assembly?

Accepted Answer

Dew point condensation

Answer

When air cools to its dew point temperature at a cold surface, water vapor condenses into liquid moisture.

Question 2

In a hot-humid climate, where should the vapor retarder be placed in a wall assembly?

Accepted Answer

On the exterior side, toward the hot exterior

Answer

In hot-humid climates, the dominant moisture drive is inward from the hot exterior, so the vapor retarder belongs on the exterior side.

Question 3

What does the term 'thermal mass' refer to in building science?

Accepted Answer

A material's ability to store and slowly release heat

Answer

Thermal mass describes a material's capacity to absorb, store, and release heat energy, moderating interior temperature swings.

Question 4

Which heat transfer mechanism does low-emissivity (low-e) window coating primarily reduce?

Accepted Answer

Radiation across the air gap

Answer

Low-e coatings reflect infrared radiation, reducing the radiative heat transfer between the glass panes.

Question 5

A HERS rater measures attic ventilation to ensure balance between intake and exhaust. What is the recommended ratio of net free area to attic floor area when using balanced ventilation?

Accepted Answer

1:150

Answer

The standard building code ratio for balanced attic ventilation (50% intake, 50% exhaust) is 1:150 net free area to floor area.

(HERS) Certified Home Energy Rating System Rater Practice Test

(HERS) Certified Home Energy Rating System Rater Practice Test

HERS Building Science Principles 2