Page 196 - Construction Waterproofing Handbook

ABOVE-GRADE WATERPROOFING 3.85

FIGURE 3.88 Basin termination waterproofing detail.
(Courtesy of C.I.M. Industries)

FIGURE 3.89 Sandwich system used for civil construction on-grade. (Courtesy of LBI Technologies)

Built-up roofing
The oldest system still commonly used today, built-up roofing (BUR), derives it name
from the numerous layers of felts and bitumens applied to a substrate. Bitumens used as
roofing membranes include coal tar and asphalt bitumens. By virtually adding layer upon
layer, this type of system eventually covers and waterproofs a substrate and associated ter-
mination and transition details.
In the past, the quality of the roofing felts used was often inadequate for in-place ser-
vice conditions. As technology advanced with other systems, BUR use declined.
Improvements in materials now used for felts, including fiberglass, has led to reacceptance
of the built-up roofing system. Field labor safety and field quality control of actual instal-
lations do, however, present problems in most BUR applications, particularly in confined
and tight areas containing intricate termination and transition detailing.