Jun 19, 2019 · Whether building new process lines or renovating existing lines, capital and operating and maintenance (O&M) cost estimates are important for project planning and implementation. The …

As a recommended practice (RP) of AACE International, the Cost Estimate Classification System provides guidelines for applying the general principles of estimate classification to project cost …

Class 4 estimates are generally prepared based on limited information and subsequently have fairly wide accuracy ranges. They are typically used for project screening, determination of feasibility, …

Nov 28, 2025 · Teams use Class 4 estimates to compare design options, test cost feasibility, and narrow down project strategies. Owners often require this level to decide if the project is economically sound …

Jun 11, 2021 · The cost estimation methods used for achieving a Class 4 estimate are virtually the same as those used in Class 5. However, factoring and proportioning are used on more specific items.

For example, a Class 4 estimate for one project may be as accurate as a Class 3 estimate for another. This can occur when the Class 4 estimate is based on a repeat project with reliable historical cost …

Class 4 – These estimates come into play when project owners are assessing a project’s feasibility. Between 1-15% of the project must be defined at this stage, which is still not much, but the cost …

Nov 7, 2025 · Class 4 estimates refine cost drivers and enable early risk assessments. This is also where early contingency discussions begin, reflecting the substantial uncertainty that still exists.

Feb 26, 2025 · A feasibility-level estimate used for project studies, alternative evaluations, and funding requests when a limited amount of scope definition is available (1% to 15%).

A Class 4 cost estimate, often referred to as a "Feasibility" or "Pre-Authorization" estimate, is a mid-level estimate used in project management, particularly within the Association for the Advancement of …