A small opening in masonry walls that allows water drainage and prevents moisture accumulation behind wall systems.

Weep Hole is a small opening in masonry walls that allows water drainage and prevents moisture accumulation behind wall systems through strategically placed gaps or tubes that provide escape routes for water that penetrates exterior wall assemblies while maintaining structural integrity and weather protection. This essential drainage component consists of intentional openings, typically 3/16 to 1/4 inch in diameter, that are created in mortar joints or through specialized weep hole products that allow water to drain from wall cavities while preventing pest intrusion and maintaining thermal performance. Weep holes are critical in masonry construction where they prevent water damage, reduce hydrostatic pressure, maintain wall durability, and ensure building envelope performance, making them indispensable for brick veneer walls, stone cladding, retaining walls, and any masonry system where moisture management is necessary for long-term structural integrity and building protection.

Weep holes are utilized in various masonry applications and drainage systems including brick veneer walls where they drain water from the cavity between the brick and backup wall, stone cladding systems where they prevent water accumulation behind natural or manufactured stone, retaining walls where they relieve hydrostatic pressure from soil moisture, window and door installations where they drain water from sill areas and frame cavities, foundation walls where they prevent water buildup against below-grade surfaces, and specialty applications including planters, pool decks, and architectural features where drainage is essential for preventing water damage and structural problems. Each application requires appropriate weep hole placement, sizing, and protection based on water loads, structural requirements, and building codes.

The types and materials of weep holes include open head joints that create natural drainage openings by omitting mortar in vertical joints, plastic weep hole inserts that provide controlled drainage while preventing pest intrusion, rope wicks that draw moisture from wall cavities through capillary action, tube-type weep holes that provide defined drainage paths with pest protection, metal weep hole covers that allow drainage while preventing debris accumulation, and specialty weep systems including adjustable, screened, and decorative options for specific applications. Weep hole type selection depends on wall system, exposure conditions, and aesthetic requirements.

Fun Fact: Weep holes have been used in masonry construction since ancient Roman times, and modern weep hole systems can drain up to several gallons of water per linear foot of wall while openings as small as 3/16 inch can provide effective drainage.

• Knot Hole
• Pilot Hole