About Retrofit Drains
After removing the existing strainer/dome and clamp ring, the retrofit/insert drain can simply be inserted into the existing roof drain pipe. These drains utilize an expansion seal that prevents water from backing up between the gap of the original drain pipe and the stem of the new insert drain. The backup seal is critical in preventing leaks caused by back flow pressure.
Various Back Up Seal Designs:
·O-Rings–Rubber O-rings are placed on the stem of the insert drain and fill the gap between the existing drain and the insert drain stem.
·Gasket–A rubber gasket with flexible ribs on the insert drain wedges between the existing drain and the insert drain stem.
·Mechanical Expansion Seal–An expansion seal is expanded by activating fasteners.
·Expanding Tape–When the protective release paper is removed, the expanding tape reacts to the moisture in the air and expands. This fills the gap between the insert drain's stem and the existing drain pipe.
Various Retrofit Drain Materials:
·Aluminum–Spun Aluminum body and strainer/dome & aluminum clamp ring
·Stainless Steel–SS body and aluminum or cast iron strainer/dome & cast iron clamp ring
·Copper–Copper body with cast aluminum or plastic dome.
·Plastic-Plastic body with plastic or cast aluminum dome.