01.3
Definition maturity and the estimate
Does the estimate state the class it was produced at, and does that class match the scope definition actually achieved?
What goes wrong without it
An estimate class is a statement about how much was known, not about how hard anyone worked. When a number produced at low definition is carried forward into a sanction paper without its range, the organisation commits to a figure that was never a commitment. The overrun that follows is then investigated as a delivery failure, which it is not.
What to examine
- Find the declared estimate class. An estimate with no declared class cannot be assured, only re-performed.
- Test the declared class against the definition deliverables actually complete at the time, since deliverable maturity is the sole primary determinant of class.
- Confirm the correct industry addendum was applied. The building and general construction ranges do not apply to transport infrastructure, tunnels, dams, or one-of-a-kind assets such as stadiums and health facilities.
- Check the accuracy range travelled with the number into the sanction paper, and whether the board saw a range or a point.
- Establish whether contingency was set at a stated confidence level, and whether anyone senior understands that a P50 estimate is designed to be exceeded about half the time.
Required by
- AACE International Recommended Practice 56R-08, cost estimate classification for the building and general construction industries, revision of 7 August 2020.
- AACE International Recommended Practice 18R-97, the process industries equivalent, 2 February 2005.
- PMBOK Guide, Eighth Edition, November 2025, which carries finance as one of its seven performance domains.
In the asset lifecycle method
The steps of the two methods that this domain examines.