California Reinforcing Steel Contractor (C-50 License) Practice Exam

Forms are the temporary molds that shape fresh concrete until it gains strength. They must be rigid, easy to assemble and remove, and economical for the job. On most projects, forms are made from wood, fiberboard, or plastic because these materials are readily available, lightweight, and can be cut and set to fit various shapes. They also release from the cured concrete relatively easily and can produce a good surface finish with proper treatment. Metal forms are used when high reuse or long-term durability is needed, but they’re more expensive upfront and less common for typical jobs. Glass isn’t used as a form material, since it’s fragile and not suitable for shaping wet concrete, and concrete itself is the material being formed, not the form.