Abstract
A ballasted EPDM single-ply roof system is extremely difficult to inspect and repair. The minimum 10 pounds per square foot of ballast, plus airborne dust, debris and residue from the ballast, create an obscuring layer over most of the roof surface. When a leak occurs in a loose-laid, ballasted EPDM roof system, extensive and costly damage to both the building interior and structure can result before the source of the leak is recognized and repaired. The nonadhered layers of membrane, insulation and vapor retarder (if any) that constitute a ballasted EPDM single-ply system offer multiple channels for water to travel laterally before entering the building. Unless the roof membrane has factory defects or was damaged during installation, the most likely cause of any roof leaks will be abuse, design deficiencies, improperly installed flashing, deteriorated flashing or membrane seam failure. This paper will focus on the following procedures for eliminating or dramatically reducing the cost of damage incurred due to leaks in a loose-laid, ballasted EPDM roof system: 1) how to recognize and repair improperly installed or deteriorated flashings before they become the source of a leak and 2) innovative techniques to simplify locating the source of a roof leak before extensive damage is incurred. The aforementioned procedures are the results of studies and field tests conducted on more than 40 ballasted EPDM roof systems ranging in age from one to 10 years. These studies have been ongoing since the date of installation for most of these roof systems. Although this paper will focus on EPDM, it should be noted that other loose-laid, ballasted single-ply membranes may share many similar characteristics and problems.
A ballasted EPDM single-ply roof system is extremely difficult to inspect and repair. The minimum 10 pounds per square foot of ballast, plus airborne dust, debris and residue from the ballast, create an obscuring layer over most of the roof surface. When a leak occurs in a loose-laid, ballasted EPDM roof system, extensive and costly damage to both the building interior and structure can result before the source of the leak is recognized and repaired. The nonadhered layers of membrane, insulation and vapor retarder (if any) that constitute a ballasted EPDM single-ply system offer multiple channels for water to travel laterally before entering the building. Unless the roof membrane has factory defects or was damaged during installation, the most likely cause of any roof leaks will be abuse, design deficiencies, improperly installed flashing, deteriorated flashing or membrane seam failure. This paper will focus on the following procedures for eliminating or dramatically reducing the cost of damage incurred due to leaks in a loose-laid, ballasted EPDM roof system: 1) how to recognize and repair improperly installed or deteriorated flashings before they become the source of a leak and 2) innovative techniques to simplify locating the source of a roof leak before extensive damage is incurred. The aforementioned procedures are the results of studies and field tests conducted on more than 40 ballasted EPDM roof systems ranging in age from one to 10 years. These studies have been ongoing since the date of installation for most of these roof systems. Although this paper will focus on EPDM, it should be noted that other loose-laid, ballasted single-ply membranes may share many similar characteristics and problems.
Date
9/1991
9/1991
Author(s)
Daniel Schumann; Richard Critchell; Larry Johnson
Daniel Schumann; Richard Critchell; Larry Johnson
Page(s)
310-313
310-313
Keyword(s)
bridging; leak; leak source; recover
bridging; leak; leak source; recover