Precast Concrete–To–Precast Concrete Facade Joints Using Precompressed Expandable Foam

■ Specimens constructed with the industry standard of dual sealant and backer rod were also tested to serve as the control specimens and benchmark for data comparison. This paper discusses precompressed expandable foam as an option for sealing the joints of an architectural precast concrete panel building enclosure (referred to as precast concrete). The building enclosure is defined as the physical component or system of components of a building that separates the interior from the exterior environment. Architectural precast concrete building enclosures provide the facade of the building with more than just the environmental separation. Architectural precast concrete has had a successful long-term track record of use for building enclosures to control water and air penetration. Precast concrete wall designs are typically specified with a two-stage sealant joint between the concrete elements. This industry has accepted and recommended this approach. All exposed joint sealants require inspection, maintenance, and repair over time. Typical sealants degrade over time, and exposure to weather and ultraviolet rays can result in delamination and, subsequently, water leakage through the joint.