Parametric estimation

Abstract

With advancements in computers and computer software, better control of project costs and construction duration can be maintained by contractors and owners. A great deal of software is now available to deal with tracking, scheduling, and detail estimating of construction projects. However, there are few programs available to generate a cost estimate from minimal details. Parametric estimation structures the detailed line items of completed projects into smaller groupings, or assemblies, with a relationship to known variables, or parameters. Through these parameters, such as gross square footage or length of pipe, a new detailed estimate can be generated from an old estimate. There are many uses for this type of estimating process. An estimator might use this approach as a quick check on a final estimate to confirm that no major cost items have been neglected. Parametric estimating can also be used to generate detail for the early stages of design when there is no formal design drawn on paper. With the use of multiple construction systems (assemblies), the estimator can perform a value analysis on the different systems to decide which is the lowest-costing system.