Project Controls and Estimation Curriculum

Estimate Class

Module from the Project Controls and Estimation Curriculum curriculum.

Module 3 - AACE Cost Estimate Classes · Learning Objectives · 1. Apply AACE Recommended Practice 18R-97 for process industry estimates · 2. Identify Class 5 (ROM), Class 4 (concept), Class 3 (budget), Class 2 (bid), Class 1 (definitive) · 3. Match class to project maturity (FEL phase) · 4. Understand expected range: Class 5 (-50/+100%), Class 1 (-5/+10%) · 5. Document basis of estimate (BOE) per AACE RP 34R-05 · AACE Estimate Class Matrix (RP 18R-97)

Class	Maturity	Accuracy Range	Preparation Effort	Typical Method	Use
Class 5	0-2%	-50 to +100%	0.005-0.5% TIC	Capacity-factored	ROM, FEL 1
Class 4	1-15%	-30 to +50%	0.01-1% TIC	Equipment-factored	Budget, FEL 2
Class 3	10-40%	-20 to +30%	0.1-3% TIC	Semi-detailed	Budget, FEL 3, FID
Class 2	30-70%	-15 to +20%	0.5-10% TIC	Detailed	Bid, EPC start
Class 1	50-100%	-10 to +15%	1-15% TIC	Definitive	Contract, change

Source: Project_Controls_Estimation_Curriculum_v1.xlsx · Sheet: Estimate Class

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