Conceptual – An estimate that is prepared during the Planning project development phase. This estimate is based on limited project scope definition (category, concepts, schematics, and location). Parametric estimating tools are frequently used to prepare conceptual estimates including lane mile factors.
Baseline – An estimate that is prepared during the Scoping project development phase. The baseline estimate becomes the budget when approved. The level of scope definition varies depending on project type, size, and complexity. A baseline estimate is most often prepared using historical bid based estimating techniques.
Updates – An estimate that is prepared during the Design project development phase. Estimate updates are based on preliminary plans and other design information. Estimate updates are used to ensure the project is within the approved budget or serve as a basis for obtaining an authorized change to the approved budget. An estimate update is most often prepared using historical bid based estimating techniques.
Engineer’s – An estimate that is prepared at the end of the PS&E phase of project development. Plans and specifications are complete. An Engineer’s Estimate is most often prepared using historical bid based estimating techniques. The Engineer’s estimate serves as a basis for obligating funds for construction and comparing with contractor’s bids.