What is the maximum spacing for open weep holes in a wall?

• A. 12 Inches
• B. 24 Inches
• C. 18 Inches
• D. 30 Inches

Answer: (B)

Open weep holes provide a drainage vent for a masonry cavity wall. They let any water that penetrates the outer wythe drain down the cavity and exit to the exterior, while also allowing air to circulate to dry the wall system. If the holes are spaced too far apart, moisture can accumulate in the cavity, leading to dampness, staining, or damage behind the finishes. Keeping the spacing to not more than two feet (24 inches) ensures there’s a continuous outlet for moisture along the wall and adequate ventilation for the cavity, promoting faster drying after rain. In practice, you’ll see these holes placed at the bottom of the veneer cavity and at intervals no greater than two feet, which is the standard maximum spacing.