Details: Plaza Drain Flashing 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. By Blackpool Roofing|2011-02-03T17:23:00+00:00February 3rd, 2011|Emergency Roofing Maintenance, Industrial Roofing, Roofers, Roofing, Roofing Industry News|Comments Off on Details: Plaza Drain Flashing Share This Story, Choose Your Platform! FacebookTwitterRedditLinkedInTumblrPinterestVkEmail