Hercules® RetroDrain

Retro fit roof drain designed to fit into existing drain leaders in re-roofing applications

One-piece spun aluminum body, heavy duty cast aluminum strainer dome, and clamping ring provide strength and durability. The Hercules RetroDrain incorporates U-Flow® Seal technology for a mechanical watertight connection to PVC or cast iron pipes to prevent water from backup damage.


Features & Benefits

  • One-piece seamless body provides strength and durability without separation of the flange from the stem. 
  • Extra large flange allows positive attachment of roof flashing membrane while the sump area facilitates drainage.  
  • Cast aluminum strainer dome and clamping ring.
  • 12-in. long drain stem accommodates most existing field conditions with longer lengths available.
  • Incorporates U-Flow Seal technology for a secure, watertight connection.
  • Also available with a plastic dome or the cast-aluminum SuperDome.
  • Saves time and money by allowing easy installation from the rooftop without disturbing occupants.




For Detailed Drawings click here.  For 3-Part Specifications click here.

Ordering Info
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OlyFlow® RetroDrains are designed to replace existing drains in reroofing 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

SKU Size Packaging Dimensional Weight Weight
HDAL3A 3" Each 32 lb
HDAL6A 6" Each 32 lb
HDAL5A 5" Each 32 lb
HDAL4A 4" Each 32 lb

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