Vertical Corner Flashing Detail

This detail provides proper application method of sheet or reinforced membrane waterproofing systems. The corner of a wall is a vulnerable location and it requires additional protection to eliminate moisture infiltration. The detail applies to interior vertical corners and exterior vertical corners.

Materials

• Flashing material: Reinforced flashing membrane required by waterproofing system manufacturer.

• Adhesive/bitumen: Adhesive or hot bitumen required by waterproofing system manufacturer.

• Tape: Butyl sealant tape

Execution

For interior and exterior corners, coat the corner and both sides 12 inches out and to the height of the vertical substrate. Embed ⅞ -inchby-⅞ -inch butyl sealant tape to the height of the vertical substrate and press it tightly into the corner. Pre-cut two 12-inch widths of waterproofing sheet to the height of the vertical substrate. Install the first piece 9 inches to the first side and three 3 inches to the second side. Reverse-install the second ply with 3 inches to the first side and 9 inches to the second side. Embed the sheets in the manufacturer’s approved adhesive or bitumen material in application rate in accordance with the manufacturer’s latest printed specifications. Apply waterproofing system over the completed vertical corner flashing detail.