Insulation, heat reflectivity, and retention in a building are classified as which type of building property?

• A. Physical
• B. Chemical
• C. Thermal
• D. Mechanical

Answer: (C)

The key idea is how heat behaves in a building. Insulation, heat reflectivity, and retention describe how heat moves, is reflected, and is stored, which are all about thermal behavior. Insulation adds thermal resistance, reducing heat flow through walls and roofs. Heat reflectivity concerns how surfaces reflect radiant heat, tied to properties like emissivity and reflectance in the thermal radiation domain. Retention speaks to how much heat the structure can store and how long it takes to gain or lose temperature, a function of heat capacity and thermal mass.

These aspects are different from physical properties (shape, size, color), chemical properties (composition, reactivity), or mechanical properties (strength, stiffness). They specifically pertain to heat transfer and storage, so they’re classified as thermal properties.