As-built vs as-maintained
Also called as-designed vs as-built
As-built is the configuration a unit had when it left the factory. As-maintained is what it is now, after field repairs, upgrades and substitutions. The gap between the two is where service mistakes and warranty cost come from.
A familiar story: a customer orders spare parts, the parts ship to the as-built configuration, and the unit in the field was converted years ago. Nobody at headquarters knew.
Closing the loop means field changes come back into the record. The payoff runs both ways: fewer wrong parts, and the ability to see which other units could use an upgrade.
Related terms
Go deeper
Last reviewed November 2026 by Element Consulting
