The purpose of the holes in the wall behind exterior siding is to provide ventilation and allow moisture to escape from the wall assembly. These holes are commonly known as weep holes or drainage holes.
Exterior walls are typically constructed with multiple layers, including an outer layer of siding or cladding, a weather-resistant barrier, and an inner layer of sheathing. Moisture can enter the wall assembly through various sources, such as rainwater, condensation, or leaks. The weep holes serve as an outlet for any moisture that penetrates the exterior siding or collects within the wall assembly.
By allowing moisture to escape, the weep holes help prevent the buildup of water within the wall cavity. Accumulated moisture can lead to problems such as mold growth, rotting of structural materials, or damage to insulation. The weep holes promote airflow and drainage, facilitating the drying process and reducing the risk of moisture-related issues.
It's worth noting that weep holes are typically found in certain types of siding installations, such as vinyl siding or brick veneer. Different siding materials and installation methods may have specific requirements regarding ventilation and drainage. It's important to follow the manufacturer's guidelines and consult with professionals familiar with the specific siding system in use to ensure proper installation and maintenance.