What architectural feature assists in controlling airflow in a building?

The vapor diffusion retarder is an architectural feature specifically designed to manage moisture movement within a building, but its role also supports the control of airflow. By limiting the diffusion of water vapor through building assemblies, it helps maintain a balanced environment, which prevents excess humidity that can lead to air quality issues and structural problems due to moisture accumulation.

Effective airflow control is essential for maintaining comfort and energy efficiency in a building. When a vapor diffusion retarder is properly installed, it not only helps to manage moisture but also aids in the overall performance of the building envelope by reducing unintended air leakage. This contributes to a more stable indoor climate, promoting energy efficiency and occupant comfort, which is critical for building performance.

The other options, while they all have some role related to air movement, do not have the primary function of controlling airflow in the same systematic manner as the vapor diffusion retarder. For instance, chimneys primarily focus on expelling combustion gases, windows and doors are openings that can facilitate airflow but do not inherently regulate it. Their presence can impact airflow, but they are not designed primarily for that purpose.