Which two materials are commonly used for thermal insulation?

Fiberglass and foam board are widely recognized as effective materials for thermal insulation due to their properties of reducing heat transfer. Fiberglass insulation consists of tiny glass fibers that trap air, providing excellent resistance to conduction and convection. It is commonly used in residential and commercial buildings, often installed in walls, attics, and floors due to its lightweight nature and ability to fit into various spaces.

Foam board, made from rigid foam materials, is another effective insulator. Its closed-cell structure minimizes air infiltration and provides high insulation values while being easy to cut and install. This makes foam board suitable for applications where space is limited or where continuous insulation is required.

In contrast, concrete and wood do not provide sufficient thermal resistance, as they are not specifically designed for insulation purposes. Steel and aluminum are conductive metals, making them unsuitable for insulation, while brick and mortar, though durable, do not inherently provide thermal resistance compared to dedicated insulation materials. Hence, the combination of fiberglass and foam board is ideal for ensuring energy efficiency and comfort in various building applications.