Best Practices - Sealing PREPRUFE® Seams Using Vee Rollers Technical Bulletin

In addition to using a traditional seam roller, we also recommend the use of a “Vee Roller” to assure the adhesion and watertightness of laps and “T” joints.

The “Vee Roller” is used to seal T-joints created when PREPRUFE® Tape is used for end laps and other details. A T-joint is formed when overlapping materials (e.g. side lap) is then overlapped by an additional layer of material (e.g. PREPRUFE® Tape from an end lap detail). Because of the “step-down” between the overlapping materials, a channel is created that requires special attention to assure a continuous seal. The thicker the materials, the larger the step-down and thus, the larger the T-joint.

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Example of a "Vee Roller"

The narrow, curved, steel “Vee Roller” is rolled along this channel to conform the PREPRUFE® Tape to the step-down. Run the Vee Roller along the edges of the overlapping material that can be seen under the PREPRUFE® Tape to achieve a proper seal.

NOTE: In addition to using the “Vee Roller” on the step-downs all PREPRUFE® membrane laps (side and end) and all PREPRUFE® Tape should still be rolled firmly with a traditional two-inch wide smooth steel roller.