National Home Inspector Practice Exam 2026 - Free Home Inspector Practice Questions and Study Guide

The joints on the exterior of the brick chimney should be concaved primarily for functional and aesthetic reasons. A concave joint allows for better water shedding compared to other joint types. This shape helps direct rainwater away from the masonry and prevents moisture from penetrating the joints, which can lead to deterioration over time.

Additionally, concave joints are often preferred because they create a smooth, finished look that enhances the overall appearance of the chimney. This styling can create a more professional and clean appearance, which is highly regarded in masonry work.

In contrast, raked joints can leave gaps that may invite moisture intrusion. Open joints could allow for significant water penetration and affect the structural integrity of the chimney, while closed joints, although they may appear neat, can trap moisture and lead to other long-term issues. Therefore, a concaved joint represents the most effective balance between durability and aesthetics for brick chimneys.