Table 15 Optimism Bias Upper Bound Guidance for Buildings Projects

Upper Bound Optimism Bias (%)22

Non-standard Buildings

Standard Buildings

39

51

4

24

Works Duration

Capital Expenditure

Works Duration

Capital Expenditure

Risk Area Contributions to Upper Bound Optimism Bias (%)23

Non-standard Buildings

Standard Buildings

Procurement

Complexity of Contract Structure

3

1

1

Late Contractor Involvement in Design

6

2

3

2

Poor Contractor Capabilities

5

5

4

9

Government Guidelines

Dispute and Claims Occurred

5

11

4

29

Information management

Other (specify)

Project Specific

Design Complexity

2

3

3

1

Degree of Innovation

8

9

1

4

Environmental Impact

Other (specify)

5

5

Client Specific

Inadequacy of the Business Case

22

23

31

34

Large Number of Stakeholders

6

Funding Availability

3

8

Project Management Team

5

2

1

Poor Project Intelligence

5

6

6

2

Other (specify)

1

2

< 1

Environment

Public Relations

8

2

Site Characteristics

3

1

5

2

Permits / Consents / Approvals

3

< 1

9

Other (specify)

1

3

Political

13

Economic

13

11

External Influences

Legislation / Regulations

6

7

9

3

Technology

4

5

Other (specify)

2