A vent pipe is a crucial component of a plumbing system that allows air to enter and exit the drainage system. This helps maintain proper pressure and prevents the buildup of harmful gases. By providing ventilation, vent pipes ensure that wastewater flows smoothly through the pipes without creating blockages. Typically made of PVC or cast iron, vent pipes are installed vertically and connect to the drainage system. They extend through the roof or side of a building, allowing gases to escape safely into the atmosphere. Proper installation and maintenance of vent pipes are essential for the overall health of a plumbing system.