Which stage of project development typically sees the final accuracy in a Class A estimate?

The final accuracy in a Class A estimate is typically achieved during the Construction Documentation phase. During this stage, detailed drawings and specifications are created, which provide precise information regarding materials, systems, and construction methods. This high level of detail allows for a comprehensive understanding of the project's costs, leading to the most refined and accurate estimate.

In earlier phases, such as Pre-Design, Design Development, and Schematic Design, the estimates are less accurate because they are based on broader concepts, preliminary designs, and less detailed information. These stages involve more assumptions and approximations, making them less reliable for budgeting purposes. Therefore, as the project progresses and documentation becomes more detailed, the accuracy of the Class A estimate improves, culminating in the final accuracy during the Construction Documentation phase.