Roof Drain with 4.00″ Gravel Stop Extension and Adjustable Extension

The combination flange clamp and gravel stop of this 15-1/4″ (390) diam. adjustable roof drain spins around a threaded extension to conform to the varying thicknesses of built up felt and asphalt in Insulated Roof Membrane Assembly (IRMA) waterproofing systems. The drain is adjustable on-site to accommodate roofs between 1-1/4″ (32) and 4″ (100) thick with up to 2-3/4″ (70) of insulation. A4″ (100) high perforated stainless steel gravel stop protects drain lines from the crushed gravel commonly installed with these roof systems along with a polyethylene dome strainer for other debris. Drain body and flange assembly are made of Duco coated cast iron.