What is the primary function of water-resistant barriers (WRB) in construction?

The primary function of water-resistant barriers (WRB) in construction is to resist bulk water while allowing moisture to escape. This design is essential because it helps protect the building structure from water infiltration that can lead to issues such as mold, rot, and degradation of materials.

While WRBs are effective at resisting water from the outside, they are also engineered to allow any moisture that may be present within the wall system to evaporate. This balance is crucial because it prevents moisture buildup, which could otherwise create hazardous conditions inside the wall cavity.

Choosing this option accurately reflects the dual purpose of WRBs: safeguarding the building from external moisture while accommodating the natural movement of moisture from within the structure. This feature helps maintain the integrity of the building and enhances its durability over time.