Basic concepts of building deck waterproofing stem from the need for economic use of limited land resources, from the advantage of thermal efficiency inherent with underground structures, and from esthetic considerations in architectural design. Plaza or terrace construction is simply a roof uniquely designed to accommodate other uses—pedestrian promenades, recreational and entertainment functions, and exhibition or parking areas—over occupied space. The most frequent problem in these types of construction is the failure to meet the fundamental need to keep water from leaking into the space below.
This paper addresses only the specification of quality and technical aspects of the design for the installation of waterproofing systems for horizontal applications. The specifier's selection of the waterproofing membrane depends on the type of substrate and on the nature of anticipated overlying components including membrane protection, insulation, drainage provisions, and wear surface, and on ambient climatic conditions and geographic location The wear surface can be monolithic or unitized.
The specifier should include requirements to protect components prior to installation and to prevent damage to the completed waterproofing membrane and overlying components.
Preconstruction quality assurance should include materials manufacturers and their applicators coordinating the surface treatment of substrate construction in order to assure compatibility of the substrate with the waterproofing membrane, and certifying the components and materials to be used. Contractor quality control should be specified to include continuous inspection of the application procedures and documentation of the installation.
The specifications must be coordinated and complementary with the drawings and details to avoid ambiguity, vagueness, and contradiction. The selected system of waterproofing membrane and related components should dictate the appropriate type of specification.
The histories of several projects will illustrate aspects of specifying building deck water-proofing.
Sources of nonpropnetary information for the design and installation of waterproofing systems include ASTM standards and the publications of trade organizations for architects, engineers, specifiers, applicators, and manufacturers. Components for the waterproofing system can be specified by use of generic standards or proprietary identifications.