One of the most critical details on remedial applications is the tie-in detail between the existing waterproofing application and the new waterproofing application.
Applications of flashing at cast-in-place penetrations (such as pipes or vents) are similar for both vertical and horizontal waterproofing applications.
Section 1503.2 Flashing: Flashing shall be installed in such a manner so as to prevent moisture entering the wall and roof through joints in copings, through moisture-permeable materials and at intersections with parapet walls and other penetrations through the roof plane.
The most important aspects of curb details are that they are designed at the proper height and there is sufficient termination of the flashing material.
Flashing terminations may be mechanically secured using metal termination bars or by stripping off into a recessed form of a reglet design. However, it is a best practice to follow termination designs that are in accordance with the material manufacturer’s recommendations.
In situations where the parapet wall extends above the maximum 12-inch flashing height and wall waterproofing is required, there are several options. In the case of concrete or masonry walls: waterproofing can be provided by installation of a membrane covering, a metal covering or a waterproofing coating.
The waterproofing substrate must be properly prepared prior to the application of the plaza drain flashing material. Any openings and/or defects in the substrate must be properly repaired.
A critical and often overlooked design detail is at the termination of a parapet coping at a wall. The most common mistake at this intersection is to allow the metal coping to but up to the wall without the application of termination metal.
