Building Code Administrators and Inspectors Florida Principle and Practice Licensure Practice Exam

What is the term for the coefficient of heat transmission through a building component?

1. Thermal conductance

2. Thermal efficiency

3. U-factor

4. Thermal resistance

The correct answer is: U-factor

The coefficient of heat transmission through a building component is best described by the term "U-factor." The U-factor quantifies the rate at which heat is transferred through a building element, such as walls, roofs, or windows, and is measured in units of heat loss per area per degree of temperature difference (typically BTUs per hour per square foot per degree Fahrenheit). Understanding the U-factor is crucial for energy efficiency in building design and construction, as it helps assess how well building components insulate against heat loss or gain. A lower U-factor indicates better insulating properties, meaning less heat is lost or gained, contributing to improved energy efficiency and comfort within the building. While thermal conductance, thermal efficiency, and thermal resistance are related terms in the context of heat transfer, they refer to different concepts. Thermal conductance measures the actual rate of heat transfer through a material, while thermal resistance quantifies a material's ability to resist heat flow—an inverse relationship to conductance. Thermal efficiency typically applies to systems or processes rather than individual building components.