Gutter RetroDrain

Its unique dimensions allow the Gutter RetroDrain to be installed within 9-in. wide box type gutters, near parapet walls or other tight areas. The patented RAC Backflow Compression Seal provides a proven plumbing connection with the existing leader pipe. Available in 3-in. and 4-in. sizes.

Features & Benefits

  • Pre-punched, 0.080-in. thick, 8-in. x 8-in. aluminum drain flange.
  • Strainer dome is constructed of 0.065-in. thick aluminum and is 8-in. in diameter.
  • Includes a 6-in. diameter, 0.125-in. thick, low profile, aluminum clamping ring that provides a tight compression for terminating for the roof system.
  • Patented RAC Backflow Compression Seal is quickly activated at drain flange level with a 7/16-in. wrench and protects the roof and building from water damage.
  • Designed to accommodate tight field conditions.
  • Saves time and money by allowing easy installation from the rooftop without disturbing occupants.
Ordering Info
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OlyFlow RetroDrains are designed to replace existing drains in re-roofing applications. Installed from the roof surface, OlyFlow RetroDrains are engineered to be installed without removing the existing plumbing or fixture while providing a watertight connection to the roof system and the existing plumbing.

As with all building materials it is the responsibility of the installer to review its usage with a design professional to confirm safety, compatibility and acceptance with the roof cover manufacturer as well as local building codes.


Ordering Information

SKUSize (in.)PackagingWeight (lbs.)
GM3 3 Each 20
GM4 4 Each 20


Physical Data:

The data below is constant for all OMG Gutter RetroDrains.

Drain Body .080-in. thick aluminum
Seal Watertight RAC Backflow Compression Seal requires 7/16-in. wrench
Flange 8-in. x 8-in.
Strainer Dome 8-in. diameter, made of .065-in thick aluminum
Stem 9-in. length
Clamp Ring .125-in. thick low profile aluminum

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