Estimating is the process of gathering information, evaluating, comparing the gathered information to figure out the constructability, duration and cost of a given project. This process covers the entire Pre-Construction phase of a project. Successful preconstruction process lays the foundation for a successful project execution.

Although the four types of estimating-CONCEPTUAL , DESIGN BUILD ,CM AT RISK, HARD BID- vary in their steps, collection and applications of information, there are three primary purpose in all types; Comparing the intended design to actual project.

  1. If the project can be built as designed, with the existing constrains and restrictions, if not, what alternatives do we have
  2. If the project can be completed within the intended time, if not, what is the realistic time frame for the project
  3. If the project can be built within the suggested budget, if not, what is the range of “doable Budget”

Since the second and third relies on the first, constructability study becomes the most important task for preconstruction phase. It is the study of existing conditions versus design to see if the project can be built  as it is. Primary goal of this process and steps to be taken is to make sure that we have gathered all the information regarding the project and all are (will be) reflected on the plans. This information is gathered through the study of existing conditions, finding out if any conflicts with the design and any constrains for the means and methods. Primary purpose is to have a concise construction plan with all the required information and details are reflected on the plans in order to minimize the RFIs , addendums and revisions at the late stage of the process. The more information we have , the better our estimate  and proposals of sub trades would be.

Based on the gathered and evaluated information, we can find out if the project needs to be in phases, if it can be built within the intended time frame.

During pre-construction phase the budget changes based on the lack of or availability of information. Once the information on constructability and duration information becomes clearer, the budget estimate would be sufficient to compare with the intended budget to see if it can be done within that budget.

Depending on the type of contract/bid, either a value engineering comes to the agenda, or price is given as estimated.