The specification section should include connection components embedded in the precast concrete, related loose connection hardware, and any special devices for lifting or erection, if required, as responsibilities of the precaster. Items to be specified in other sections include building frame support provisions required to support units, including portions of connectors attached to the structure, joint sealing and final cleaning and protection.
The responsibility for supply of precast concrete support items to be placed on or in the structure in order to receive the architectural precast concrete units depends on the type of structure and varies with local practice. Clearly specify responsibility for supply and installation of hardware. If not supplied by the precast concrete fabricator, list supplier and requirements in related trade sections.
The type and quantity of hardware items required to be cast into precast concrete units for other trades should be clearly specified. Specialty items should be required to be detailed, and supplied to precaster in a timely manner by the trade requiring them. Verify that materials specified in the section on flashing are galvanically compatible with reglets or counterflashing receivers. Check that concrete coatings, adhesives and sealants specified in other sections are compatible with each other and with the form release agents or surfaces to which they are applied.
Items mentioned in the Guide Specification as supply and/or installation by others should be mentioned in the specifications covering the specific trades. Such items may include:
Cost of additional inspection by an independent testing laboratory, if required.
Hardware for interfacing with other trades (window, door, flashing and roofing items).
Placing of precast hardware cast into or attached to the structure, including tolerances for such placing.
Joint treatment for joints between precast concrete and other materials.
Access to building and floors.
Power and water supply.
Water repellent coatings.
Plant-installed facing materials such as natural stone and clay products.
Guide Specification Development:
These Guide Specifications have been developed jointly by PCI, Gensler and the American Institute of Architects (AIA), Master Systems publishers of MASTERSPEC®.
Performance specifications may be employed with good results as long as the architect identifies the purpose to be served and includes appropriate safeguards such as pre-qualification of precasters, pre-bid approval of materials and surface finishes, careful review of shop drawings, and architect’s approval of initial production units.
Prescriptive specifications often contain inflexible to stringent requirements which can adversely affect a projects budget and delivery schedule. A common use of prescriptive specifying is with pre-engineered cladding systems. Typically an owner will engage a design firm to engineer a cladding system in order to