Definition: Underbuilder, also known as a general contractor, is responsible for building or renovating structures. They often work on large, multi-story buildings and are involved in many different phases of construction, including designing, bidding, managing subcontractors, overseeing the installation process, and performing inspections to ensure quality and safety. Underbuilders typically have a background in architecture, engineering, or construction management, and they may also hold specialized licenses such as a general contractor's license or a building permit holder's license.