Smith® Overflow Drain, Standpipe, Series: 1070, 3 in Nominal, No Hub, Cast Iron Drain, 15-1/4 in Dia x 10-1/4 in H
Used in flat roofs of any construction where a constant height of water is desired on the roof. It is also used on conventional roofs as a safety overflow, which receives water only when the build-up is greater than the setting of the standpipe. Standpipe type water dam can be cut to achieve various water depths on the roof.