Which type of rigid polystyrene is commonly used in construction?

The choice of white or blue board is correct because these types of rigid polystyrene are specifically designed for insulation applications in construction. They are commonly referred to as expanded polystyrene (EPS) or extruded polystyrene (XPS), which are preferred for their thermal insulation properties. These boards provide effective insulation against heat loss and are moisture resistant, making them suitable for both above-grade and below-grade applications, such as foundation walls, roofs, and various building assemblies.

In contrast, the alternatives do not represent rigid polystyrene products used in construction applications. Green board is primarily a type of moisture-resistant gypsum board used in areas prone to high humidity, which isn't related to rigid polystyrene. Pink board, although it refers to another brand of XPS insulation, is not the commonly recognized term compared to white or blue board. Yellow board does not typically refer to a standard type of insulation material in construction and may not have the same properties as the specified blue or white rigid polystyrene.