North Point Plumbing on Instagram: "How a Loop Vent System Works – Explained by North Point Plumbing Loop vent systems are an innovative solution in commercial plumbing for venting multiple fixtures especially in island sinks and areas without easy wall access. Instead of using a traditional vent stack, the loop vent forms a continuous circuit of pipe that rises above the highest flood level rim and reconnects to the drainage system, maintaining proper air pressure and preventing siphonage in th