Decommissioning Insight 2015

B. Association for the Advancement of Cost Engineering Classifications The five estimate classes in the AACE Cost Estimation Classification Matrix are determined by level of ‘project definition’ with consideration to a set of secondary characteristics.

1

2

Primary Characteristic

Secondary Characteristic

Level of Project Definition (expressed as % of complete definition)

Expected Accuracy Range Typical Variation in Low and High Range

3

End Usage Typical Purpose of Estimate

Methodology Typical Estimating Method

Estimate Class

Capacity factored, parametric models, judgement or analogy Equipment factored or parametric models Semi-detailed unit costs with assembly level line items Detailed unit costs with forced detailed take off Detailed unit cost with detailed take off

4

L: -20% to -50% H: +30% to +100%

Class 5

0% to 2%

Concept screening

L: -15% to -30% H: +20% to +50%

5

Class 4

1% to 5%

Study or feasibility

L: -10% to -20% H: +10% to +30%

Budget authorisation or control

Class 3

10% to 40%

6

Control or bid/tender

L: -5% to -15% H: +5% to +20%

Class 2

30% to 70%

7

L: -3% to -10% H: +3% to +15%

Check estimate or bid/tender

Class 1

50% to 100%

8

9

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