The Cast Iron Soil Pipe Institute is a not-for-profit trade association, and its membership is comprised of the domestic manufacturers of cast iron soil pipe & fittings. The Institute maintains two standards that are referenced in every plumbing code in the country and regularly inspects each member foundry to verify compliance to the US standards. We are the go-to source for recommendations, best practices, and suggestions regarding sizing, installation, and maintenance of drain, waste, and vent systems and cast iron soil pipe & fittings. Cast iron’s longevity, durability, and sustainability make it the logical choice for DWV systems. Our team is strategically located across the country and is ready to provide education as we strive to improve life safety, resiliency, & performance of plumbing in building construction.