BackerBead® Drip Flashing - 3-1/2" Flange

Drip flashing with built-in closed cell backer rod

BackerBead® Drip Flashing - 3-1/2" Flange is designed to provide positive drainage above exterior window and door openings while also providing a caulk tray at the top of window and door frames for the proper seal and added moisture protection.


Eliminates the need to install a backer rod separately, as the product features a factory-applied backer rod that is affixed to the vinyl Drip Flange and set for accurate jointing. This accessory allows the installer to create a “gap” on the wall without the hassle of aligning it in the field, thereby saving time and materials.  The Drip Flange is recommended over window, door heads, short roof flashing, or underneath stone for a brick-ledge condition.  Punched holes near top of attachment flange facilitates easy fastening.

Features / Benefits:

  • Combination Bead - Reduces steps in the field installation of Drip Flashing and separate backer rod. Ensures backer rod is installed around all door and window openings.
  • Improved Quality - Factory-applied blue backer rod with preset width and depth to ensure proper caulk gap for sealant application. When the gap is properly caulked, the blue backer rod will no longer be visible.
  • Separation of Dissimilar Materials - Properly terminates stucco and mortar at window and door frames. (ASTM C926)
  • Sealant Compatibility - Closed-cell backer rod compatible with elastomeric, silicone, urethane and other cold-applied sealants.




Prior to setting the Drip Flange, clean all surfaces to receive the bead and remove any debris. Refer to sealant manufacturer’s recommendations on caulking this gap. Dry off surfaces. Have the backer rod touch the adjacent surface continuously.  Make sure the Drip Flange component on the Head opening extend 1/2" wider than the casing bead intersection below, terminating from the jamb.

BackerBead® Instalación


ASTM & Code Standards:

  • Vinyl Material: Complies with ASTM D1784 and ASTM C-1063, Table 1, PVC for exterior use.
  • Backer Rod: Closed cell material per ASTM C1330, square, flexible continuous lengths of extruded polyethylene foam used as a backing material.
  • Passed ASTM E331 - Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference.  This ASTM performance covers the determination of the resistance of exterior windows and doors to water penetration when water is applied to the outdoor face and exposed edges simultaneously with a uniform static air pressure at the outdoor face higher than the pressure at the indoor face.   Stucco was tested in this condition both with the BackerBead® and caulking, vs. no bead and caulked gap, which did not pass the E331 test.  Test results are available upon request.
  • SDS & Product Certification Information

Product Submittal Sheets

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Product Code Description
BackerBead Drip Flashing - 3-1/2" Flange BackerBead® - Drip Flashing - 3-1/2" Flange

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