Which of the following is a commonly used material for roofing insulation?

Fiberglass is widely recognized as a commonly used material for roofing insulation due to its excellent thermal performance and affordability. It is made from fine strands of glass that provide effective insulation by trapping air, which reduces heat transfer. This characteristic makes fiberglass a popular choice among roofers looking to improve energy efficiency in buildings. Its lightweight nature also allows for easier handling and installation compared to some other insulation materials.

While cellulose is known for its environmentally friendly properties, primarily used in residential applications, it may not be as common in roofing insulation specifically. Wood chips and concrete do not serve the same purpose; wood chips are typically used as mulch or in landscaping rather than insulation, and concrete is a structural material rather than an insulator. Therefore, fiberglass stands out as a key choice in the realm of roofing insulation.