Cost escalation

An estimate is priced at a stated base date; the project spends money over years. Escalation bridges the two. It is calculated by spreading the estimate over the expenditure schedule and applying forecast indices — construction cost indices, commodity forecasts, labour agreements — appropriate to each cost category, because steel, cable, fuel and labour do not move together.

Escalation is deliberately kept separate from contingency: contingency covers uncertainty about what the project is, escalation covers movement in what things cost, and merging them makes it impossible to tell later which one was wrong. In volatile markets escalation can rival contingency in size, and contract drafting decides who carries it — a lump-sum contractor prices it in; a cost-plus owner pays it as it happens; indexed contracts share it by formula.

The characteristic error is anchoring: pricing tomorrow's project on today's quotes and treating the result as conservative. A multi-year project priced without escalation is not a tight estimate — it is an estimate for a project that will be built entirely this month.